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rstrucks
10-01-2010, 01:02 AM
What axles are recommended for different set ups, wheelin styles, tire size, terrain...?

What axles have you run, broken, upgraded to, swapped in....?

What aftermarket shafts, joints, lockers or gears have fixed a weakness on your axles?

What HD axles under 'XX-'XX year trucks are a bargain?

Try to keep this based on personal experience. The more info you can provide the better - spline counts, wms to wms measurements, bolt patterns, shaft/joint material, etc.... Dana 35 talk will not be tolerated.

Jeeptech01
10-01-2010, 09:04 AM
Subscribed. Interested in the fronts!!

ATL ZJ
10-01-2010, 10:39 AM
To run the trails I like to run (mix of Southeastern trails) you need a tire in the 40"+ range, decent gearing, and wheelspeed on demand. In order to have all those things and not break, it usually means one ton axles with chromoly shafts. I think that is the commonly accepted minimum required equipment for this part of the country unless you have an ultralight rig with deep gearing or you want to stick to less challenging trails... which there is nothing wrong with.

To date I've broken:

stock waggy d44 outer
yukon waggy d44 4340 outer
8.8 ARB, sort of (failed shortly after new owner had it)
806-x spicer non greasable dana 60 U-joint
yukon 35 spline inner (short side)- twisted at the splines- more on why this is "broken" later on

Since the "what size tire can I run on my 30/44" question has been beat to death, a more interesting direction for this thread is why axles break at all. R&P size is the most obvious limitation, but shaft when shafts themselves break, when is the break due to diameter, shape, or material? And when is a smaller diameter shaft stronger than a larger diameter shaft of the same spline count, and why? These are the kinds of questions that help us make good decisions about aftermarket shafts. I could answer my own questions but I think it'll be more interesting if other people post up instead of me just blabbering on...

rstrucks
10-01-2010, 10:59 AM
I haven't broken that much stuff - luckily. I did break a couple of D30 u-joints which took out both the inner and outer shafts when I was on 35's. I also need to go up in pinion yoke size to 1350. I crushed the needle bearings in my 1310 series u joint last trip out. It didn't break but it shows there is a little too much load on too small a joint. The old joint was a TW's Gold Seal joint and the new one is a Spicer - we'll see if it holds up any better.

IMO 33's are the safe limit for a Dana 30. A fully polished 30 may last for a while with larger tires but it's just a matter of time.

The factory D44a is in the same boat - 33's.

Dana 44's are good in the 35" range. A front 44 can be made to work with 37's but it's pushing it as far as reliability goes.

A Ford 8.8 can work well with up to 37's.

I'd save the one ton axles for tires 36" and larger due to ground clearance and weight issues.

Obviously you can make anything work and make anything break depending on tire size and driving style so the above is a generic guide.


As far as bargain axles go, I think the Super Duty (98-04) front 60's are a steal. Stock they are nothing too special but they can be upgraded to be fairly strong. I am running what is essentially a SD front with high steer and 35 spline shafts and I don't have that much in it. I paid about $150 for the axle and spent money on shafts, Warns, and machine work to run high steer and 5 on 5.5" wheels. For rear axles, well they are all pretty cheap but a 14 Bolt is tough to beat.


Since the "what size tire can I run on my 30/44" question has been beat to death

That is why this is the TOTM - so when a newb asks that exact question he can be pointed to this thread and have all his questions answered (pointing and laughing is optional:tease: ). :D

Jeeptech01
10-01-2010, 11:45 AM
Lets also consider failures of parts due to the weakness of others. For instance housing flex allowing ring and pinion or carrier damage.

ed: and things we can do to combat these issues

CrawlerReady
10-01-2010, 12:22 PM
Alright, I can add to this thread a bit from my experience.

Moab has traction. Wheel speed isn't really a huge thing, but there are still situations where you need it and trails that require a little skinny pedal. I ran Dana 44's front and rear for 2 1/2 years with 35's and 37's. I broke 2 axle u-joints in that time which in turn caused the ears to break of the shaft each time. If you're going to run D44's (or most any axle choice for that matter) CARRY SPARE SHAFTS. The time will come when you break one. Shafts only get weaker over time after they've been twisted enough.

One of the BEST things I ever did was used full-circle clips on my u-joints. From the time I did that on my front D44, I never broke a shaft on 37's until I went to a sticky 37. From my experience, the biggest reason why people break shafts is the c-clip holding on the u-joint cap pops off, letting the cap slowly slide out of the shaft, and then breaking on the knuckle. Usually this will also break the ears on the shaft, if it doesn't, they're sure to be bent/weaker.

Most trails (85%) in Moab you will probably be just fine running Dana 44's and 35-37s. However, if you like the skinny petal or you plan on running a bigger tire than 35's, then 1-ton axles may be what you're looking for. I went to 1-ton axles after I snapped 3 outer Chrome-Moly D44 shafts and blew up my rear R&P, spool, and 1 rear shaft on my rear D44 with my 37" stickies.

Currently I run 40" tires with a Dana 60 front. 35-spline Chrome-Moly outers and stock non-neckdown 35-spline inners. My rear axle is only a Ford 9" (so not technically a 1-ton axle) but I've got a Yukon Nodular 3rd, and Moser 35-spline Alloy shafts and spool. So far it's been good for quite a bit of gas pedal on the 40's, we'll see how the rear R&P hold up when I put some 40" stickies on it though.

As for aftermarket shafts, front shafts are available in Chrome-Moly, rear come in Alloy. The difference is that Alloy allows for more "twist" than Chrome-Moly, so for rear shafts axle manufacturers design them to take more abuse rather than just shatter when you really hit the skinny pedal. Not something you have to look out for, but just some info that may give you a better understanding of different materials when looking at aftermarket shafts.

ATL ZJ
10-01-2010, 12:24 PM
Lets also consider failures of parts due to the weakness of others. For instance housing flex allowing ring and pinion or carrier damage.

ed: and things we can do to combat these issues

Trussing from C to C or flange to flange is important if you are going to get serious about doing any go-fast or wailing on your rig on rockcrawling trails.

Full floaters are more forgiving for obvious reasons, and allow for shafts to be made out of superior material.

Extra pinion supports like in the 14b minimize ring and pinion deflection, and high pinion gearsets help add strength in frontend applications.

ATL ZJ
10-01-2010, 12:45 PM
As for aftermarket shafts, front shafts are available in Chrome-Moly, rear come in Alloy. The difference is that Alloy allows for more "twist" than Chrome-Moly, so for rear shafts axle manufacturers design them to take more abuse rather than just shatter when you really hit the skinny pedal. Not something you have to look out for, but just some info that may give you a better understanding of different materials when looking at aftermarket shafts.

I realize this is going to be a pretty basic thread but it's still worth calling things by the right names. Chromoly is a mix of different alloys. Most chromoly front shafts are 4340 and most aftermarket semifloat rear shafts are 1541 which is a carbon steel with some alloy added. Over the years I have heard that 1541 is a better choice for shafts that bear the load of the rig. Most front axles (30 excluded), use real hubs so the spindle bears the corner weight, so aftermarket front shafts are generally 4340 or 300m.

Twist or deflection has a lot to do with material, heat treating, and shaft diameter and neckup... this thead (http://www.pirate4x4.com/forum/showthread.php?t=917868) is a great discussion about shaft technology today and the importance of deflection over ultimate stength. Carry on...

SirFuego
10-01-2010, 01:03 PM
Here is a list (and approximate dates) of stuff I've broken on my HP30 (I've had zero issues with my 8.8):

May 2009 -- Broke a stock D30 shaft just past the splines (most common point of shaft failure). The shaft broke at an angle. As it was rotating, the "long" end of each side of the broken shaft pushed off of each other and caused ring gear deflection, which took out the Ring, Pinion and Carrier. This failure was due to my tire being wedged between two large rocks and trying to "bump" it out. I upgraded to RCV shafts since my mentality was immediately turned away from the "if I break a shaft, I'll just replace it and keep on wheeling" mentality.

September 2009 -- Broke a crosspin in three on Otter's in Rausch -- but didn't realize it until later in the weekend. I was trying to climb a ledge with my front tire as my rig was pointing downhill, so there was a LOT of force on that tire. After that trail, I heard a "clicking" coming from the CVs when turning. My buddy is running the RCV Dana 60 shafts and has experienced a similar thing -- so I kept on wheeling. Later in the weekend my driveshaft was spinning, but my tires were only doing so intermittently. We determined it was something internal.

The verdict was that I broke my crosspin in three. The cross pin was banging off of the pinion -- and the sound was reverberating down the tube and out at the CV -- which is why it sounded like the CVs were clicking. This ended up taking out the ring/pinion and carrier. I upgraded to a hardened crosspin from Richmond, hoping this would help.

August 2010 -- After a good year of wheeling (with some other non-axle issues), I went through a log trap at a local place. It got nice and slicked up and required some throttle. I got in the habit of letting off of the trottle as soon as I felt my front end come off the ground -- but I failed in this case. The force from the shockload of the front end hitting the ground while I was on the throttle twisted the carrier beyond it's limits -- took out the R&P, too. It even damaged a spacer in my locker. I had known for a while that with my style of wheeling, 1 tons were a necessity, so I just decided to cut my losses and am saving up for big boy axles.

I'll add a "post-assessment" later, but I will say that I think that my HP30 failures were due to my mentality on the trails. If I didn't let myself get into precarious situations on harder trails, I'm sure I could have made the HP30 last a LOT longer on 35s...

CrawlerReady
10-01-2010, 01:03 PM
Cam yeah, you're correct. I should've said 4340 and 1541. Companies just refer to 4340 as Chrome-Moly and 1541 as Alloy from what I've seen.

edit: side note, I've always known it to be Chrome-Moly. Is it actually Chromoly? Not that this is a lot of tech, but different companies use it both ways...

AgitatedPancake
10-01-2010, 01:11 PM
I ran the stock D30 with 33" MTR's and broke a CV like it was nothing, so I built myself a front LP44 a couple years ago.

I'd rate the a bone stock dana 44 to a 36-37" tire if you drive with a little finess. I broke a U-joint last year with zero wheel speed, I had a tire jammed up in some rocks really good, gave it gas from a stop and just heard a pop. Mine was kind of an odd break, it only snapped 1 side of the u-joint, but that let it stretch the ears of one of my inner shaft. There is an asterisk with the break, and that is the U-joints were the ones that were in the axle when I pulled it from the junk yard, which looked like they could have been 15 years old. I replaced it and tacked the caps on the loose ears, and have had a good time rompin on it with 36's (BUT I'm still not locked)

http://sphotos.ak.fbcdn.net/hphotos-ak-ash2/hs329.ash2/60932_448258652611_502627611_5237314_7621300_n.jpg


Ahhh I found a pic of where I broke. I broke the drivers side u-joint exactly where I am in this picture, you can see how wedge that tire is. It could NOT move.

http://www.agitatedpancake.com/random/jeep/fordyce/DSC03770.jpg

I'm running a 35 spline rear 9" like Tyler is, so I'm not even getting close to pushing the limit of it with the 36" tires right now.

The rear 44a I'd rate strongly for 33's, and 35's with a concious mentality about it. I ran it on 33's for years locked with no issues. I moved up to 35's and had no issues for a while, until it happened. I had an axle shaft breakage while stuck in a hard rock obstacle at barrett lake. I limped it out 5 miles on the broken shaft, threw a replacement in (that my dad brought from sac!) sitting in the staging area the next morning, then ran the 6 mile trail in to save the weekend, and back out. That trip was the end of my 44a, I pulled the shafts and found the broken shaft peices had destroyed the housing around the carrier bearing, so the housing was trashed. I pretty much expected that though, the scary thing though is that BOTH the axleshafts had twisted splines. Even the one I put in 12 trail miles ago...

Now I'm building a high pinion 609 front so stay tuned :D :D

Here's a pic of my 44a shafts when pulled. As said, one only had the one trip on it where I was a very concious driver!
http://www.agitatedpancake.com/random/jeep/9/DSCN3695.jpg

ATL ZJ
10-01-2010, 01:23 PM
Cam yeah, you're correct. I should've said 4340 and 1541. Companies just refer to 4340 as Chrome-Moly and 1541 as Alloy from what I've seen.

edit: side note, I've always known it to be Chrome-Moly. Is it actually Chromoly? Not that this is a lot of tech, but different companies use it both ways...
I think the correct spelling is chromoly, but I have friends who are MEs that type it out as chro-moly. I guess any spelling is acceptable if it communicates the idea clearly...

CrawlerReady
10-01-2010, 01:24 PM
Yeah, just curious.

Jeeptech01
10-01-2010, 01:55 PM
IMO 33's are the safe limit for a Dana 30. A fully polished 30 may last for a while with larger tires but it's just a matter of time.


A Ford 8.8 can work well with up to 37's.



Are we talking about low pinion or 30's in general?

I believe the weak spot of the thirty besides the small gearset and carrier is the weak housing. The tubes are tiny and there isnt very much ribbing on the pumpkin. From the research I've done sleeving the tubes, a simple truss and good aftermarket cover will go a long way without dumping too much coin into a turdy.

Cheap 8.8 insurance: Weld tubes to the pumpkin.

CrawlerReady
10-01-2010, 02:22 PM
Cheap 8.8 insurance: Weld tubes to the pumpkin.

I think that is a good idea for ANY axle personally. I've welded the tubes to the pumpkin on every axle I've swapped in. My brother pulled a tube on his D35, and since then, every axle gets burned together.

SirFuego
10-01-2010, 02:44 PM
IMO 33's are the safe limit for a Dana 30. A fully polished 30 may last for a while with larger tires but it's just a matter of time.
I would agree with this. I ran my HP30 pretty hard on 33s with stock shafts. That bump up from 33s to 35s is where the axle CAN hold up, but you need to be VERY cautious on the trails. If you upgrade tires to make your current trails/obstacles/lines easier, then you can probably have it hold up. If you upgrade to 35s so that you can run more difficult trails/obstacles/lines, that's when it becomes "a matter of time".


I think that is a good idea for ANY axle personally. I've welded the tubes to the pumpkin on every axle I've swapped in. My brother pulled a tube on his D35, and since then, every axle gets burned together.
Agreed. My HP30 and 8.8 both had welded tubes. My new axles will definitely have the tubes welded to the housing.

fredr1980
10-01-2010, 03:01 PM
One of the BEST things I ever did was used full-circle clips on my u-joints.

I would definitely have to agree with this, but only if you stick to 33's or less on a D30! Prior to doing this I broke 5 shafts on the old D30, two on 32's and three shafts on 35's, four of which where short side shafts and I suspect the caps came loose after spitting out the c-clip which then let the u-joints snap the ears off the axles the fifth shaft was a short side stub that snapped at the splines. I heard pop but couldn't see any of the damage and ended up loosing a wheel driving down the road from the trail. After I took a dremel to to the shafts to accept full circle clips the first axle break was a catastrophic one, didn't break a u-joint but I believe either the teeth on the ring and pinion let go, which then completely destroyed the ARB and then the short side inner at the splines by the locker, or it could have been the axle shaft inner which took out the ARB and then the fact that the carrier was shattered then took out the gears... either way it wasn't good. Putting full circle clips on the u-joints shifted the "weak spot" to something else which resulted in MORE carnage in my situation.
http://i101.photobucket.com/albums/m47/fredr1980/P4090157.jpg
Now I'm running a HP D44 narrowed to wagoneer width with warn inner and outer shafts and yukon superjoints. Only issue I've had blowing out one of those oldshool warn hubs (non-premium) that I picked up the the JY when I first built the axle. In that particular situation the tire was bound up pretty bad and the weakest point gave out which I'm fine with that. The rear I'm still running the Ford 8.8 with minimal issues, bent a flange on an axle shaft about a year ago, also right before the GSR I opened it it to inspect everything and noticed that the "shims" had walked out of place on the pass side of the carrier. Put them back in and it's all good so far but I did get two loud pops during GSR that I've never heard before that I don't believe to be locker related so I have to check that out. In all fairness it did get me through the trail and the 5 hour drive back home so it's probably nothing.

Fred R.

dp96zj
10-01-2010, 03:06 PM
For future reference, I think this thread should be linked in here:
http://www.mallcrawlin.com/forum/showthread.php?t=19280

That aside, sure, tons are great, but what about the little guys? :tease:

Ex: I'm on a budget, mine is my daily driver. Sure, it may be built in the future, but as of now, I don't have the time or money to go LA's and tons. For the guys that are hovering around 33" tires or so, if a rear axle swap is desired, the cheapest and easiest route would be an 8.8 swap. They're cheap, a shit-ton stronger than a turd-5, and much more reliable than 44a's. The aftermarket support is MUCH better for an 8.8 over a 44a or d35, and it's been proven on this board that these axles, when built, can hold up to some romping on 35"+ tires. At the very least, the tubes should be welded and quality brackets used.

The easiest place to find a decent 8.8 would be under 1996+ Ford Explorers, as these came with disks and 31 spline shafts. Most came with 3.73's, some had 4.10's. For a front axle to compliment the 8.8, the cheapest and easiest bolt in axle would be an HP30. This combo should hold up to 33's.

Here are some more links for future reference if someone is looking into an 8.8 swap:
http://www.mallcrawlin.com/forum/showthread.php?t=2880
http://members.cox.net/quanno/ford88.html
http://www.jeepsunlimited.com/forums/showthread.php?t=371713


The axle shaft strength tested by Warn Ind:
F8.8= 6,500 (lb. ft.)
D44= 4,600-5,000 (lb. ft.)
D35C= 4,000-4,300 (lb. ft.)
Dana 35 rear axle COT: 870 MOT: 3480
Dana 44 rear axle COT: 1100 MOT: 4460
Ford 8.8 28spline COT: 1250 MOT: 4600
Ford 8.8 31spline COT: 1360 MOT: 5100
Dana60 semifloat COT: 1500 MOT: 5500
I'm done.

SirFuego
10-01-2010, 03:20 PM
Twist or deflection has a lot to do with material, heat treating, and shaft diameter and neckup... this thead (http://www.pirate4x4.com/forum/showthread.php?t=917868) is a great discussion about shaft technology today and the importance of deflection over ultimate stength. Carry on...
I've been following that thread a bit. It's interesting that there is a LOT of research on rear axles due to car racing, but very little (relatively speaking) seems to be known about front axles.

I was reading BillaVista's Axle Shaft Bible (http://www.pirate4x4.com/tech/billavista/PR-BV60/index1b.html) (which was written a while ago) and it talks about "equal torque". The basic idea, from what I understand, is that both axles should react "equally" in terms of how much they twist under the same amount of torque. As a result, in an offset differential, the shorter shaft needs to have a smaller diameter than the longer shaft. I would be very curious for folks to take a caliper reading on the short and long inner shafts in various applications and see if the shaft diameters differ. There never really seems to be any discussion about this...

rstrucks
10-01-2010, 03:35 PM
I realize this is going to be a pretty basic thread but it's still worth calling things by the right names. ...

Don't let the basicness (new word) stop you from bringing some good tech. :)


Now I'm building a high pinion 609 front so stay tuned :D :D



What are you going to run for outers? King pin stuff?


Are we talking about low pinion or 30's in general?

I believe the weak spot of the thirty besides the small gearset and carrier is the weak housing. The tubes are tiny and there isnt very much ribbing on the pumpkin. From the research I've done sleeving the tubes, a simple truss and good aftermarket cover will go a long way without dumping too much coin into a turdy.


I was referencing 30's in general. I also think that the 30 is pretty well matched from the factory and it is what it is - just a small, lightweight axle.


Also, axle shafts should have raised splines as to not create a weak point at the inner end of the spline. Maybe a clearer way of saying it would be - the diameter of the splines should be larger than the smooth shaft just to the inside of the splines. That way you just have added material for the splines instead of cutting into the shaft to create them thus eliminating the weakness of cut splines.

SirFuego
10-01-2010, 03:38 PM
Here is my "post-assessment" in regards to my previous post about my HP30 failures:

1) A truss (even a mini-one) that covers as much of the axle as possible is necessary. This greatly reduces the chance for movement inside the axle -- which causes failure.

2) 4.10s allow more teeth engagement between the ring and pinion. Yes, I went through 3 ring and pinions running the D30, but based on my assessment (validated by others) the ring and pinion was never the CAUSE for the failure. I don't know that I would ever run 4.88s in a D30. FWIW, I did get my second R&P cryo treated, but like I said, the R&P was never the cause of the failure, so I don't know if the cryo treatment helped any.

3) If you run chromolly shafts, a carrier replacement locker (detriot, grizzly, arb, zip, etc.) is probably a better choice than a lunchbox locker. When I dismantled my internals after my last break, it was very obvious that the stock carrier couldn't handle the shock loads.

4) If you run a lunchbox locker, get a replacement hardened crosspin from Richmond. Well worth the $15-$20 it costs.

5) I'm not a big fan of u-joints. I really think that CVs are going to become more commonplace and more affordable in the future -- I'm anticipating a viable competitor to RCV to crop up in the next couple years. I noticed a LOT less wheel hop running CVs. In addition, you don't need to worry about "laying off" if you are at full steering lock. Finally, when a CV does break, it basically just freely spins, so you don't have any axle ears to break or push apart (potentially causing worse failure). Don't get me wrong though, high quality U-joints and shafts still are more than sufficient -- some even claim that they broke RCV's then switch to 300M u-joints without any problems (heck, I'm admittedly debating what to do about this for my upcoming build right now). That comment alone might be the sole reason I might be wrong about CVs becoming more popular if they don't come down in price.

ATL ZJ
10-01-2010, 03:48 PM
I've been following that thread a bit. It's interesting that there is a LOT of research on rear axles due to car racing, but very little (relatively speaking) seems to be known about front axles.

I was reading BillaVista's Axle Shaft Bible (http://www.pirate4x4.com/tech/billavista/PR-BV60/index1b.html) (which was written a while ago) and it talks about "equal torque". The basic idea, from what I understand, is that both axles should react "equally" in terms of how much they twist under the same amount of torque. As a result, in an offset differential, the shorter shaft needs to have a smaller diameter than the longer shaft. I would be very curious for folks to take a caliper reading on the short and long inner shafts in various applications and see if the shaft diameters differ. There never really seems to be any discussion about this...

I'm not aware of any mainstream shaft manufacturers that build their short side shafts to a smaller diameter, although some may. I know yukon doesn't. And their neckdown profile is just plain bad. I was running a pair of their 35 spline chromo inners and twisted the short side shaft past its range of elastic deformation. I swapped a 10 factory shaft in, which is shaped properly, and is very arguably stronger due to its design. Here's a pic for reference.

http://img.photobucket.com/albums/v125/atlzj/IMG_0514.jpg

The 10 factory shaft (on the right) has an operating diameter that I measured as .017" smaller than the yukon shaft for the same application next to it (on the left). The operating diameter of the 10 factory shaft is also smaller than the root of the splines, like it should be, according to carroll smith and a lot of other people way smarter than I am.

Look where the yukon bent. At the stress riser where the splines and spider gears of the diff engage. If the operating diameter had been smaller, I think the load would have been distributed more evenly over the entirety of the shaft and maybe the long side shaft too, and the shaft may have even been able to deflect a greater number degrees due to the smaller diameter. I can't be sure whether the 10 factory shaft would have suffered the same fate but I have a hunch that it would have taken more force or more repeated stress to do it.

SirFuego
10-01-2010, 04:02 PM
In regards to my comment on axle diameters. Assuming a 35" long shaft that is a diameter of 1.5", I calculated that an 18" short side shaft would need to be 1.27" for the same theoretical "twist" characteristics. For reference, a D44 30 spline shaft is about 1.31" and a D30 shaft is 1.13".

IMO, whether manufacturers "neck down" their shafts depends a lot on cost/benefit. From my understanding, a neck down shaft is more expensive and complicated to manufacture, so the added strength it gives might not be worth the extra cost to the manufacturer. In addition, assuming the Yukon shaft splines weren't twisted, 99 out of 100 random people would probably look at your picture and immediately gravitate towards the Yukon shaft, because it's counterintuitive to most people that a narrower shaft will (in theory) hold up better.

dp96zj
10-01-2010, 04:14 PM
Very interesting data posted in that p4x4 link. I went ahead and watched the video coverage of them breaking the different shafts, shown here if you don't feel like searching. The actual shaft testing starts about 46 minutes in:

http://www.pirate4x4.com/tv/live12.php


So although the Yukon "Hardcore" shafts stood up to 6100 ft lbs, they only had 55* of deflection, while the Ten Factory shafts were 5100 ft lbs and nearly double the deflection. Or take the Superior import, with 5800 ft lbs and 130* of deflection! In terms of axle shafts, I'm assuming most people would sacrifice torque in order to achieve more deflection? ...as shown by Cam's photos above.

On a side note, do you think that Yukon is intentionally putting out shafts with higher torque yields, because people tend to look at torque rather than deflection?

EDIT: I think that it's funny that in the video the Yukon shaft split lengthwise, not directly at the splines. Right before that, Randy said they're made to break specifically at the splines :rofl:

biggoofy
10-01-2010, 04:25 PM
I really dont have much to add here since everything I know has already been covered but I would love to see some simple and easy truss ideas for the 8.8 and hp30 as im about to swap them into my rig!

SirFuego
10-01-2010, 04:31 PM
That aside, sure, tons are great, but what about the little guys?
Rear: 8.8" or D44. For an 8.8 upgrade, I would recommend welding the tubes as well as a truss (I recommend that for any axle to be honest). In addition, I would also look into making a "ramp" under the pinion to get rid of any hangup points on the diff. I never did the latter and wish I did.

Front: HP30 or some type of Dana 44. If you know you are eventually going to 1 tons, I would just stick with a 30 and stay at 33s if you don't want to polish the 30. If you know that you aren't going past 35s or 36s, I'd just build the 44 and be done.

dp96zj
10-01-2010, 04:33 PM
I really dont have much to add here since everything I know has already been covered but I would love to see some simple and easy truss ideas for the 8.8 and hp30 as im about to swap them into my rig!
There are a few examples in the links in my post on the first page. But in all honesty, it'd be easiest for you to take some time and search/find out what people have used an 8.8 by looking through build threads. Not to mention, you can get the basic idea of an 8.8/hp30 truss from looking at any trussed axles, really.

CrawlerReady
10-01-2010, 04:47 PM
http://www.pirate4x4.com/tv/live12.php


So although the Yukon "Hardcore" shafts stood up to 6100 ft lbs, they only had 55* of deflection, while the Ten Factory shafts were 5100 ft lbs and nearly double the deflection. Or take the Superior import, with 5800 ft lbs and 130* of deflection! In terms of axle shafts, I'm assuming most people would sacrifice torque in order to achieve more deflection? ...as shown by Cam's photos above.

I agree, I watched that vid a few days ago and those Sup. Import shafts seem to be the best all around.


On a side note, do you think that Yukon is intentionally putting out shafts with higher torque yields, because people tend to look at torque rather than deflection?

I'm sure that's the case. I know when I looked at Cam's photo, all I noticed was that the Ten Factory was a lot smalller. I'm always pulled towards bigger shafts.............

dp96zj
10-01-2010, 04:49 PM
I'm always pulled towards bigger shafts.............

Nevermind, I won't say anything. This is supposed to be a tech-thread :D

BigDaveZJ
10-01-2010, 05:05 PM
My rig originally had a 35 and LP30. I swapped out the 35 pretty early, and went to a HP30 a couple years ago when I went from 33's to 35's and regeared to 4.56.

The only issue I've had with the 8.8 was bending a shaft about 5 years ago. It was a full throttle assault on Double Whammy on Golden Spike. Basically very high traction, two decent sized ledges at once, at a medium incline. I didn't have a truss on it at the time as I was on short arms still, but added one when I went to long arms.

I've kept the 30 open up front because it's rare that I really need the front locked on the trails I run, and I don't want to dump selectable locker money into a 30, and with an automatic locker I'm just asking to break something up there. For shafts I'm just running stock TJ shafts and they have held up so far, but I've been intentionally easy on the front axle to prolong their life.

I don't see myself going any bigger than 35's, so if the 30 ends up not getting the job done I may do a HP44 at some point, but the cost there is big so it will take a significant failure on the 30.

Mtn WJ
10-01-2010, 07:43 PM
I think it makes a difference in axle swap choices based on if you are doing both axles all at once or if you are doing one at a time. It also makes a difference if you are in dire straits because your Jeep is down or if you have time to plan and get parts as you go.

My rear axle was a situation where I was down and didnt want to fix the D35, however I had time to wait for my new axle to come in becaue my Jeep is not a daily driver. My front axle was a different story as I collected parts for 3 years and finally have it under my Jeep as of last month.

I have a Currie HP 9 with Detroit and Chromoly 31 spline shafts in the rear. it is also trussed when I did the TNT long arms. I ordered it new specific to my application after breaking 2 shafts in 2 days on a Dana 35 at a GSW in Moab. I weighed a lot of options before going with Currie.

Some of the options were go with F150 8.8 and have re-drilled for 5 on 5 pattern. This would have been 65WMS-WMS and the WJ is 63.5 which means spacers up front. Go with Explorer 8.8 and put spacers on the rear. Spacers are ok with me. The Isuzu D44 is same width as WJ but 6 bolt lugs.

However going through the options a HP axle would reduce the need for a SYE in my 242 TC. Saves me 4-600 on the SYE and not to mention a new Drive Shaft at 3-400.

Obviously the WJ uses the rear tone rings for speedo. I wired the front TRs to the rear input and discod the ABS CPU. This has worked for my speedometer for 5 years now with no problem.

I spent just under 3k including shipping for the Currie. I figured an 8.8 built up will be close to 2k with similar internal hardware. Figure buy diff, Locker, shafts, gears plus set up labor, mounting hardware etc.

I went somewhere different up front. I was able to get a custom HP 30 housing that was re-tubed for WJ width and had the Cs set for proper pinion and caster based on my lift height. I got the housing before the JK axles were an option. I liked the idea of the HP 30 because I could re-use the internals like my ARB, shafts, 1 ton steering and I would still have the ABS rings for the Speedo. Again saving me the SYE and Drive shaft costs.

I ended up with one of the more over built Dana 30s I know. I bought some new parts, some used parts, did some horse trading and etc. It has 30 spline ARB, 30 spline chromoly shafts with 760 ujoints, trussed, akebono calipers, stillen rotors, 1 ton steering OTK and is trussed. Drives great because a near perfect pinion angle and near perfect caster. I guess my weakest links are the ball joints and the R/P. However the HP30s are stronger and I have only replaced 1 set of BJs in 80k miles at 75kmiles. I run 33s with 4.56:1 gearing and pretty satisfied with the trails I run with them.

I previously had 4.10s with the 33s and was pleased with the hwy performance. However I was a little short on crawl ratio and regeared to 4.56s. So far I have just barely broken in the gears but the hwy performance is better with less hunting between 3 and 4th gear. I have not wheeled with the new front axle and gears to comment there. Should be good but just not enough break in miles yet.

I did pay to have the axle completed as I have limited free time these days and that does add to the build costs. However in any other option it would cost me too.

Corey Jpranger did a great job on the build.

If you are dong a WJ all at once I suggest going with an older F150 9 inch rear / HP D44 front combo from the same donor. Put in a SYE with speedo output and call it a day. Will save you some money and head aches.

I like the Dana 60 and 14 bolt idea too. However there is a limited amount of room with the rear gas tank and some clearance issues up front too. Takes more planning in other words.

I will say with WJs be sure to do your homework first.

Keith

AgitatedPancake
10-01-2010, 08:42 PM
If you are dong a WJ all at once I suggest going with an older F150 9 inch rear / HP D44 front combo from the same donor. Put in a SYE with speedo output and call it a day. Will save you some money and head aches.

I will say with WJs be sure to do your homework first.


Agreed! I've put thought into it too, and if doing it all at once and not going with tons, the HP44 and 9" are the perfect combo for a WJ. They give you a liiiittle extra width, and all the strength benefits! 5 on 5.5 wheels are way easy to come by too.

Jrgunn5150
10-01-2010, 08:54 PM
I've only blown one ujoint in my life lol. TJ Rubi, I guess they use wax to hold the caps on from the factory?

Anyhow, I'd like to learn more about cryo, doesn't it make the metal more brittle?

Mtn WJ
10-01-2010, 09:03 PM
So I am an idiot. I just sold my used Crane diff cover to someone off of another board. I sold it because I thougt it had the filler hole down low for LP axles. I figured it was ok because I have a warn guard that has room for either style diff filler hole. Well for some reason the Crane I just sold has the filler inlet in the same spot as the HP cover. I only noticed this when I cleaned up the crane for the buyer. I already made the commitment to the guy who drove over hear. Even thought I was pissed at myself internally. The crane is much nicer than the Warn I am keeping. Like I said do your homework.

slim616
10-01-2010, 10:06 PM
One thing to also keep in mind when deciding your tire size and axle size is your motor size. I ran 36s on a 30/8.8 with no issues when I had a 4.0 motor. I upgraded to.5.2 with the same set up and blew a 30 shaft every other trail.

Though I run 60 s now I do have to say that stock 8.8 took every thing I could throw at it. Even when I had to do stuff in 2wd because of broken front shafts.

When I get around a real key board ill go into a little more detail on real world cost of building 1tons on a budget. It's always the little stuff that you over look in the planning stage that throws you over budget.

SirFuego
10-01-2010, 11:12 PM
Anyhow, I'd like to learn more about cryo, doesn't it make the metal more brittle?

Actually, the exact opposite -- it makes the metal softer. This allows the metal to "give" a bit more during shock loads. As a result, cryo'd gears tend to wear faster. Usually, when cryo'ing gears, the metal is heat treated first to reduce the overall hardness of the metal, then it is cryo'd afterwards. I had a HP30 R&P cryo'd, but I can't really comment on how effective it actually was since I my R&P always failed due to another part failing internally.

If you get it done at a place like Longfield, they will ask you if you DD your vehicle or not. A non-DD vehicle gets the full cryo treatment since r&p wear isn't going to happen much on the trails. A DD'd vehicle has one of the processes removed to reduce the wear on the R&P.

http://www.pirate4x4.com/forum/showthread.php?t=607601&highlight=cryo

Kauzi Zj
10-02-2010, 12:33 AM
OK just to throw another question out there, because I'm no tech...and really depend on the information I get here and talking with some of you guys when we are out wheeling...

Along with the "low budget" argument, I would also like to add, that My ZJ is being built for "multi-purpose" use. I want a dependable daily driver, that behaves well on street, and mild expedition wheeling (similar trails to your San Juan trip Dave), but can also perform well in Moab, meaning I would like to know its capable of really handling Pritchett Canyon, Area BFE, Moab Rim etc...

I have three possible options, I have a friend willing to sell me an HP 44 and 9" out of a 78 F-150, but I may be able to get my hands on A 60 and 9" out of a 72 Ford 3/4 ton. The third option would be 86 Waggy 44 and 8.8...I know im going to be swapping gears and buying lockers for either option...so I will be going 4:11 gears, and mechanical locker in the rear, selectable up front.

My current specs: 94 ZJ 5.2 Limited
6.25" lift, long arm front adjustable short arms rear
Some trimming, running 33's

I will be running 35's and already plan on buying new wheels, so bolt pattern doeskin matter, other than front and rear need to match.

My biggest concern with full width, is the additional width, how will that affect the street driving? Can I with different wheel spacing lessen the notice-ability of the wider axles?


OK experts....

BigDaveZJ
10-02-2010, 01:00 AM
John,
I think your ultimate goal is about the same as mine, without the daily driver aspect. Although with the Super Duty getting up there in mileage I may need to rely on the ZJ as a DD here and there until I can swing the $$ for something else.

I would do the 9/44 combo myself. The Waggy 44 is low pinion, and bolt patterns won't match up to an Explorer 8.8.

Remember with wider axles you can negate some of the width by changing up the backspacing on the wheels. And the wider stance should make the rig a bit more stable too.

Joe Lynch
10-02-2010, 02:23 AM
we need to get some 609 tech in here as that seems to be the ultimate axle, especially for our rigs and a good alternative to 1 tons if your runnng 35's and you don't want to be stuck on every farkin rock on the rubicon.

AgitatedPancake
10-02-2010, 02:54 AM
Not many people have 'em under their trucks, but I'll let ya know lol! FearTheDentist had his 309 (lol) that had the housing break...egh lol! I'll be working with osme tight spaces on my WJ, should be a fun challenge

IndyZJ
10-02-2010, 03:27 AM
My ZJ is being built for "multi-purpose" use. I want a dependable daily driver, that behaves well on street, and mild expedition wheeling (similar trails to your San Juan trip Dave), but can also perform well in Moab, meaning I would like to know its capable of really handling Pritchett Canyon, Area BFE, Moab Rim etc...

I have three possible options, I have a friend willing to sell me an HP 44 and 9" out of a 78 F-150, but I may be able to get my hands on A 60 and 9" out of a 72 Ford 3/4 ton. The third option would be 86 Waggy 44 and 8.8...I know im going to be swapping gears and buying lockers for either option...so I will be going 4:11 gears, and mechanical locker in the rear, selectable up front.
My biggest concern with full width, is the additional width, how will that affect the street driving? Can I with different wheel spacing lessen the notice-ability of the wider axles?


This is how I'm building my current YJ project - fun and easy to drive on the street with the ability to reliably run moderate trails without any trouble on 35-37s. I'm running 5.13s to keep the trans as happy as possible, and highly recommend running at least 4.56s on 35s for the same reason, especially with a Chrysler OD. This is all behind a 5.3 with an auto, and the weight should be similar to an equivalently built ZJ.

It's getting a '78 F250 hp44 up front with 1/2 ton hubs/ spindles to match the rear. That gives me a HP center with a lot of extra material/ housing strengh (for a 44) and 3", 0.50" wall tubes. With Superior shafts and decent joints, I don't see this being a problem for anything in the 37" and down range. The selectable hubs, bigger brakes, and stronger BJs and tubes on 44s are all big advantages over D30s.

For the back it's getting a '79 F150 9" with a Detroit and 31 spline shafts for ease of getting/ finding replacements. I'm eventually going to go to a Yukon 3rd member, but the stock unit will work for now. With good shafts and a stronger 3rd, this will be completely reliable, too. Ford 60s can be good rear axles, but I would only run one with 35 spline shafts and it isn't much stronger than an equivalently built 9". The 60 does seem to have a huge advantage if you wanted to run an ARB, though.

This will be a pretty evenly-matched setup that doesn't sacrifice much ground clearance for anything below 37s, which are the biggest I want to run to keep local wheeling spots challenging. It is about as good as "1/2 ton" setups get, IMO.

You will love the stability that even a 5" wider axle will give. Of course, if you want you could run 5" of backspacing and tuck the wheels right back under the Jeep, but I would suggest going with the added stability.

Oh, AFAIK, all F250s of those years got 60 rears. Only a couple specific models got a 60 front, so 8 lugs and 3" tubes does not guaranty it's a 60.

Edit: fawk this is a long post. One more thing for now - Don't get a 44 with cast wedges. There is no axle tube going through the wedges and the tubes are smaller and thinner than some others, like the one I'm running.

Kauzi Zj
10-02-2010, 11:24 AM
John,
I think your ultimate goal is about the same as mine, without the daily driver aspect.

Thanks for the info Dave, I think I was pretty much leaning that way...just basically trying to get trusted input to let me know I'm doing it right...


I guess I should clear this up...its not actually a daily driver, but more or less when I'm home, sometimes I like to drive it around town, but as close as I live to Moab, I usually drive it down there, and want to be able to keep doing that...it will probably still get more overall mileage off road than on...but I want it safe, stable, comfortable, however you want to say it, on the road too...

Mtn WJ
10-02-2010, 12:38 PM
MY WJ is not my DD either. However I drive it to trails and tow a pop up camper. I built it as an adventure rig that is a capable off roader. This means it needs to drive very well on the highway too and be stable enough to carry a large canoe on the roof while pulling a trailer. These factors greatly influenced my choice in almost everything I did to it.

I want to keep it that way too. Not interested in a tow rig/trailer. My Jeep/camper is my RV in other words.

Jrgunn5150
10-02-2010, 04:43 PM
I like Ryans idea of the SD axles, they are plentiful and cheap.

Is the D50 a 44 r&p with 60 outer's? Or is it the other way around? Cuz that could meet alot of peoples small tire needs fairly cheap.

Jeeptech01
10-02-2010, 04:48 PM
I can contribute some 44a info. This is more for the WJ guys since IMO it would be better to swap in an 8.8 if you have a ZJ. But anything is better than a 35 so..

The 44a is a fairly stout axle and as stated previously will stand up to 33's without issue.Also known as a 44hd it has a large gearset with a pinion similar in size to a dana 60. The major drawback is the alum housing which tends to flex and cause parts breakage. It is aalso quite easy to get large gashes in the housing from rocks etc. The other issue is again due to the alum housing and that is that it tends to eat carrier bearings.

Housing fix: Aftermarket steel cover, Truss ( WJ's will need to run on the bottom to avoid clearance issues with the tri link balljoint) Skid plate up to the yoke.

Bearing fix: If you have an unmolested 44a replace the carrier bearings and subtract .002 of shim to lessen the preload on the carrier. If not measure pttr without the carrier in. Then set up the carrier preload to add 10 inlbs to the ttr. FYI new dry pinion bearings when setting up the pinion in a 44a should yield 13-16 inlbs pttr.

Heres a pic of the 44a truss I built for my 44a. I followed the contour of the pumpkin all the way across and it is 1" at its narrowest point. Then capped it off with flat bar. The skid is welded to the flat bar cap and uses a 4" exhaust clamp u bolt at front welded through two holes. Materials were 6"x 1/4" and 2" x 1/4 probably cost me $30.

http://i420.photobucket.com/albums/pp286/jeeptech01/00%20WJ/102_6649.jpg

http://i420.photobucket.com/albums/pp286/jeeptech01/00%20WJ/102_6650.jpg

SirFuego
10-02-2010, 04:55 PM
That truss looks nice. IIRC, a bottom truss is technically stronger than a truss above the axle.....

....but IMO I would avoid a truss below the axle tubes for our sport. Every inch of ground clearance counts and you can still make a very stout axle with nothing except the pumpkin below the axle tubes.

That said, I dig the ramp below the pumpkin. I guess technically it sacrifices some ground clearance, but sacrificing a bit of ground clearance is sometimes OK for the sake of getting rid of a hang up point.

IndyZJ
10-02-2010, 05:04 PM
I like Ryans idea of the SD axles, they are plentiful and cheap.

Is the D50 a 44 r&p with 60 outer's? Or is it the other way around? Cuz that could meet alot of peoples small tire needs fairly cheap.

Neither. The D50 has its own unique R&P and carrier (9" IIRC). On that note, there's a guy on pirate4x4 selling kits to put D50 gears in a HP44, along with a kit to put D70 gears into a 60 and 80 gears into a 70HD.

D50s do use 60 outers for the most part. At least in the TTB versions, the spindles were a little different, with the 50s having less of a lip on the inside edge to engage the knuckle because its caliper brackets were part of the knuckles vs. the 60 having a seperate caliper bracket. I think the SD 50 and 60 outers are the same, but I could be wrong here.

I agree on the SD axles. They regularly go for about ~$500 a set around here. I would not be afraid to run the balljoints and unit bearings on anything lighter than a SD.

AgitatedPancake
10-02-2010, 05:57 PM
Another nice thing about running unit bearings is the added allowance for running a high backspacing wheel. Normal D60 hubs have so much stickout, the unit bearing style would allow 5-6-7" backspacing wheels to be used if wanted without the hub sticking out abnormally past the wheel

Jeeptech01
10-02-2010, 08:55 PM
That truss looks nice. IIRC, a bottom truss is technically stronger than a truss above the axle.....

....but IMO I would avoid a truss below the axle tubes for our sport. Every inch of ground clearance counts and you can still make a very stout axle with nothing except the pumpkin below the axle tubes.

That said, I dig the ramp below the pumpkin. I guess technically it sacrifices some ground clearance, but sacrificing a bit of ground clearance is sometimes OK for the sake of getting rid of a hang up point.

Thanks! I really wanted to do one on top that utilized the mounting points of the balljoint but I also wanted a skid and the only other way I've seen them attached was via the cover bolts which IMO = fail. FWIW the only real clearance lost is whats on the sides of the pumpkin. There is a large stiffening rib at the back edge of the diff that is covered by the truss so clearance loss below the pumpkin is around 1/2" or less including the thickness of the plate.

?? Could someone post up the years and models the Ford HP44 was used in and which ones had the welded on wedges. Im considering looking for one for the XJ just in case. I'd want to narrow it to a width close to the 8.8. I know most people go waggy width but Im not sure how that compares to the 8.8

ELLLLLIOTTTTT
10-02-2010, 09:21 PM
That truss looks nice. IIRC, a bottom truss is technically stronger than a truss above the axle.....



Never really thought about it, but why is it stronger on the bottom?

Jeeptech01
10-02-2010, 09:31 PM
I would imagine it is because the center piece is pushing up against the pumpkin rather than being pulled away from it. But that is just speculative.

Jrgunn5150
10-02-2010, 10:46 PM
Good info on the SD axles!

As for hp44's I picked up a HP44/9 combo for my pickup to SAS it, out of a 78 Bronco and the radius arms are cast FWIW. I think 77 to 79 are cast, not sure though. Ford does alot of wierd things too.

BigDaveZJ
10-03-2010, 01:02 PM
Never really thought about it, but why is it stronger on the bottom?

I remember reading something similar at one point. I think it had to do with building a JeepSpeed rig so the strength was a bit more important than the ground clearance.

Kauzi Zj
10-03-2010, 01:09 PM
Ok, because Im trying to learn as much about this as possible I have 2 questions, why does welding the tubes help, and how and why does a truss on an axle increase strength, I was under the understanding that the breakages are generally internal moving parts, so how does strengthening the housing help?

BigDaveZJ
10-03-2010, 01:18 PM
John,
The tubes are already welded to the housings a little bit, but typically it's just a couple plug/rosette welds. By welding the tube to the housing where the tube actually enters the housing you can greatly decrease the chance of spinning the tubes in the housing.

The truss basically makes sure that the axle stays straight and true.

If you visualize the forces applied to the axle the truss will add a bunch of strength to the housing to keep it from bending.

https://www.4wdfactory.com/store/product_images/f/img_0697__80079.jpg

SirFuego
10-03-2010, 01:26 PM
Ok, because Im trying to learn as much about this as possible I have 2 questions, why does welding the tubes help
On most axles, the axle tube is usually just pressed into the housing with a couple welds holding the tubes in. It is possible that given the right situation, a tube can "spin" in the housing. Welding the tubes to the center section basically means that the welds need to break (unlikely) before the tube spins. If a tube spins, it can throw off your axle bracketry.


, and how and why does a truss on an axle increase strength, I was under the understanding that the breakages are generally internal moving parts, so how does strengthening the housing help?
Strengthening the housing prevents it from flexing due to the vigors of being offroad. When you set up a ring and pinion, they need to be setup so that the gears mesh properly. When a housing flexes, it can cause the ring and pinion to "deflect" temporarily (think of both tubes bending upwards at the same time) -- which can sometimes be enough to throw them off to the point that they break.

Another thing about a truss is that it prevents the axle tubes from bending during a hard hit or jump. If the truss, however, doesn't span as far as it can (flange to flange in the rear or C to C in the front), the tubes will just try to bend where the truss ends. This happened to a friend's axle who was just running the Clayton's truss. On a coil spring setup, though, it can be difficult to design a truss that spans the whole ale. A bent tube puts more stress on the axle shafts. More stress on the axle shafts makes them more prone to breaking.

As for the Top vs. Bottom truss, I've been told that a bottom truss is stronger by other people with racing backgrounds. From my understanding, the forces are better distributed on a bottom truss given the expected forces seen on an axle during jumping, drop offs, etc.

AgitatedPancake
10-03-2010, 01:28 PM
Aaactually dave you proved the point perfectly with that post. That style 9" has the axle tubes that are literally butted up to the center section and welded up, you can see the seams in that picture. That truss is the perfect solution, because it helps prevent failures like Brian (FearTheDentist) did with his currie 9"...

http://www.mallcrawlin.com/forum/attachment.php?attachmentid=4954&stc=1&d=1260380910

http://www.mallcrawlin.com/forum/attachment.php?attachmentid=4955&stc=1&d=1260380910

JohnBoulderCO
10-03-2010, 03:05 PM
I'd want to narrow it to a width close to the 8.8. I know most people go waggy width but Im not sure how that compares to the 8.8

I have a HP44 out of a F250 (78,79) that was narrowed to Waggy width = 62.5" with a 5x5.5 bolt pattern. That's close enough for the WJ. I measured the width and here is another source. http://www.universityofjeep.ca/wag_front_d44_install.html

The axle has the thick walled tubes, but I still added a TnT Truss. It came with Superior alloy shafts, an ARB and CTM's.

I matched my Explorer 8.8 by using Spidertrax 1.25" wheel adapters (5x4.5 to 5x5.5).

I like it being a HP axle, added strength and that it has hubs, so I have zero drive line vibes at 80mph.

A pretty strong axle combo (HP44 and 8.8) for 35"-37" tires and you can get off the shelf axle shafts, as opposed to having custom width axles.

Mtn WJ
10-03-2010, 03:19 PM
John, the axle you have is in my opinion is the perfect solution for WJs up to 37 inch tires or so.

BigDaveZJ
10-03-2010, 03:22 PM
Aaactually dave you prooved the point perfectly with that post. That style 9" has the axle tubes that are literally butted up to the center section and welded up, you can see the seams in that picture.

D'oh. Dunno WTF I was thinking, I knew that, lol. Editing post now.

Jeeptech01
10-03-2010, 09:27 PM
I have a HP44 out of a F250 (78,79) that was narrowed to Waggy width = 62.5" with a 5x5.5 bolt pattern. That's close enough for the WJ. I measured the width and here is another source. http://www.universityofjeep.ca/wag_front_d44_install.html

The axle has the thick walled tubes, but I still added a TnT Truss. It came with Superior alloy shafts, an ARB and CTM's.

I matched my Explorer 8.8 by using Spidertrax 1.25" wheel adapters (5x4.5 to 5x5.5).

I like it being a HP axle, added strength and that it has hubs, so I have zero drive line vibes at 80mph.

A pretty strong axle combo (HP44 and 8.8) for 35"-37" tires and you can get off the shelf axle shafts, as opposed to having custom width axles.

Thanks for posting that. So yours had the welded on wedges then? It appears that with 1.25" spacers the exploder 8.8 will only be .25" narrower than the waggy width hp44. I'll be keeping an eye out on my local CL.

IndyZJ
10-03-2010, 10:56 PM
Thanks for posting that. So yours had the welded on wedges then? It appears that with 1.25" spacers the exploder 8.8 will only be .25" narrower than the waggy width hp44. I'll be keeping an eye out on my local CL.

F250 = no wedges, but there is a good amount of "extra" casting on the driver's side for the leaf spring perch that could probably be cut off like on a 60. There is a lot of extra material on the f250 center section, and the tubes are beefy, especially compared to a f150 stuff. I have both in the garage - I was building the front of my YJ around the f150 axle with cast wedges, but when I went to fill it with fluid, it started leaking at the tubes and plugs welds. It apparently spun the tubes at some point, because upon closer inspection I could see that the plug welds were boogered up and it was leaking at those, too. Thankfully it was free...

It's not worth getting retubed, but maybe I'll make a super cheap 44/9" or hp30 with 44 Cs and knuckles out of the extra junk I've got sitting around for the ZJ. In case anybody's interested, 44 and 9" spiders are somewhat interchangeable. I don't know if it would work as an open dif, but it's definitely close enough to weld together, so it's possible to built a 44/9 with no aftermarket parts - you just have to figure out something for seals.

rstrucks
10-03-2010, 11:41 PM
Never really thought about it, but why is it stronger on the bottom?

I think it's because plate steel is stronger in tension than in compression, making it easier to fold the steel on top than it is to pull it apart on the bottom...... in theory.

Correct me if I'm wrong.

Jeeptech01
10-04-2010, 10:23 AM
F250 = no wedges, but there is a good amount of "extra" casting on the driver's side for the leaf spring perch that could probably be cut off like on a 60. There is a lot of extra material on the f250 center section, and the tubes are beefy, especially compared to a f150 stuff. I have both in the garage.

So candidates for the hp44 are as follows

F250 (years?) much beefier housing
F150 78-79
Bronco ?years

I have been doing a bit of searching but I take what I read on the net with a grain of salt. Most guys on here, I'll take them at their word. Dont want ya'll to think Im being lazy.

Would there be room to set the f250 housing up for coils links etc once narrowed?

ed: Found this local. Am I headed the right direction?

http://tampa.craigslist.org/hil/pts/1972008256.html

or this http://tampa.craigslist.org/pnl/pts/1947182467.html looks like it still has the radius arms on it.

SirFuego
10-04-2010, 10:45 AM
I think it's because plate steel is stronger in tension than in compression, making it easier to fold the steel on top than it is to pull it apart on the bottom...... in theory.
Yes, I couldn't think of the exact reasoning I was told, but that definitely sparked my memory and remember hearing that same thing. That said, a top truss is strong enough (and more desirable) for what we do.

fredr1980
10-04-2010, 04:05 PM
So candidates for the hp44 are as follows

F250 (years?) much beefier housing
F150 78-79
Bronco ?years

I have been doing a bit of searching but I take what I read on the net with a grain of salt. Most guys on here, I'll take them at their word. Dont want ya'll to think Im being lazy.

Would there be room to set the f250 housing up for coils links etc once narrowed?

ed: Found this local. Am I headed the right direction?

http://tampa.craigslist.org/hil/pts/1972008256.html

or this http://tampa.craigslist.org/pnl/pts/1947182467.html looks like it still has the radius arms on it.

F250 (years?) much beefier housing = 77.5 - 79 all have 3"x .5" tubes (pre-77 D44's from F250's are low pinion)

F100/F150 = 71-77, all have 2.75"x.5" tubes (78 & 79 had the wedges cast on and weaker tubes 1/4" IIRC), also IF you are not using anything from the knuckles out (going with chevy flat-tops, small bearing spindles and Ford 5x5.5 rotors instead) then go with a get something that is pre-76 as these had drums and usually go cheaper because of that.

Bronco ?years - none - Early broncos had low pinion D44's and the 78-79 broncos have the same axle as the F150's

There is room for coils on a narrowed F250 D44 as that is the axle that I currently have (narrowed to wagoneer width). I'm using a TNT customs truss with integrated mounts but even then there is still space, the only issue that you will probably run into as I had this issue with mine is that the lower control arm mount on the driver's side is going to be about 1.5-2" into the cast section, I just removed the cast in the area in-order to fit the mount. HTH.

Fred R.

IndyZJ
10-04-2010, 04:48 PM
Find out what kind of high steer arm is on the F250 axle. It could be a decent deal for $300 or so if the arm and machining are good. That F150 44 will have cast wedges. IIRC, I gave $200 for a complete stock F250 44.


F250 (years?) much beefier housing = 77.5 - 79 all have 3"x .5" tubes (pre-77 D44's from F250's are low pinion)

F100/F150 = 71-77, all have 2.75"x.5" tubes (78 & 79 had the wedges cast on and weaker tubes 1/4" IIRC), also IF you are not using anything from the knuckles out (going with chevy flat-tops, small bearing spindles and Ford 5x5.5 rotors instead) then go with a get something that is pre-76 as these had drums and usually go cheaper because of that.

Agreed. Also, the F150 spindles, caliper brackets, hubs, and discs will bolt onto the F250 flat-top knuckles to get a 5x5.5 BP. That is what I'm using just because I had the F150 stuff and it means buying fewer parts. Some guys say the Chevy knuckles are stronger, but I've never personally seen anybody have a problem with the Ford stuff on a 44.

Jeeptech01
10-04-2010, 05:12 PM
Thanks for all the info guys. I definitely feel a bit more educated now.

Cody
10-04-2010, 05:39 PM
I don't have time to read every post ahead of mine, but I'll post my experience.

I ran a hp44 from a 78.5 full size bronco in my old buggy on 37's. Rig probably weighed in the neighborhood of 4000-4500 lbs.

From memory, over about 2 years I broke: (I posted my actual totals a few years ago, but I can't find it--but I'm pretty sure this is right)

18 shafts
12 joints
maybe 30 hubs? Probably more once I switched to Superwinch hubs which 'usually' broke before anything else did. I preferred to swap a hub with a lifetime warrant than a shaft on the trail, + a few hours of my time running around trying to find more once I get home.

Stock 44 shafts aren't up for the task of anything larger than 35's IMO. To echo what Tyler said, full circle clips make a big difference. I used to tack weld the caps on all of my joints instead, but I didn't have to worry about messing up the grease seals or anything since no shaft would last longer than a few weeks. Without a full circle clip or welded caps, a spicer 44 ujoint wouldn't even get me through Pritchett. My problem was almost always the joint failing and taking the shaft out with it, although I did shear 2 outers right at the flange (at the same time even), which was kind of cool I guess.

When I switched to Warn/Yukon alloys hafts (I had Warn outers, Yukon inners) and Bobby Long Ujoints, I never had any other problems. I was also a little less likely to hammer on the expensive shafts since I couldn't afford to replace them, so that might have had something to do with it.

I had a 9" rear, 31 spline stock shafts, in the same rig and never broke those shafts.

I currently run the same style 44 in my ZJ with Warns and CTM's. It was on the rig when I bought it and if I didn't have Warns and CTM's, I don't think the 44 would hold up to my 35's and 5000# + ZJ. With that said, once you spend the coin on a 44 and purchase the upgrades shafts and joints, you could have had a front 60. So I say do it right the first time.

My position has always been the same. If you're wheeling hard enough to break a 30 and you NEED more strength, you need a 60. Otherwise, you're going to spend a lot of $$$ trying to get the 44 to hold up. If you aren't breaking 30 parts but want some of the other advantages of the 44 (bigger ball joints, ring gear, tubes, width etc), then maybe a 44 swap makes sense. Just don't go flogging it thinking that the 44 is some sort of middle ground in strength between a 30 and a 60. Without upgraded shafts, it isn't.

Jeeptech01
10-04-2010, 08:30 PM
My position has always been the same. If you're wheeling hard enough to break a 30 and you NEED more strength, you need a 60. Otherwise, you're going to spend a lot of $$$ trying to get the 44 to hold up. If you aren't breaking 30 parts but want some of the other advantages of the 44 (bigger ball joints, ring gear, tubes, width etc), then maybe a 44 swap makes sense. Just don't go flogging it thinking that the 44 is some sort of middle ground in strength between a 30 and a 60. Without upgraded shafts, it isn't.

That is an interesting take on the 30 44 60 question. I honestly figured that the 44 WAS the middleground in strength between the 30 and 60. If I would need to chromo the 44 I cant justify the expense of the 44 over just chromoing (yea new word) the 30 and saving the ground clearance.

Cody
10-05-2010, 02:35 AM
That is an interesting take on the 30 44 60 question. I honestly figured that the 44 WAS the middleground in strength between the 30 and 60. If I would need to chromo the 44 I cant justify the expense of the 44 over just chromoing (yea new word) the 30 and saving the ground clearance.

Agreed. I've also seen about 500 broken 44 shafts for every dana 30 ring gear/ball joint/tube failure I've been around. 30 and 44 basically run the same shafts and joints.

it usually runs fine
10-05-2010, 02:46 AM
The main reason I chose a 44 was to get selectable hubs so I could run a partially welded front end and still street drive my jeep. The second reason was eliminating the crap unit bearing. The third was whatever stenght gains I might get. The fourth was stronger brakes. The fifth was I hate having to say " Naw man i still have the stock 30 in the front".

IndyZJ
10-05-2010, 03:32 AM
That is an interesting take on the 30 44 60 question. I honestly figured that the 44 WAS the middleground in strength between the 30 and 60. If I would need to chromo the 44 I cant justify the expense of the 44 over just chromoing (yea new word) the 30 and saving the ground clearance.

IMO, the biggest advantages of a 44, especially a hp44 over a 30, is a stronger center section and R&P so you don't go pulling a SirFuego all over the place if you upgrade the shafts and joints, beefier Cs and knuckles, selectable hubs, better steering options, and bigger brakes. .

I agree with Cody that in stock form, the overall strength is on par with a 30 due to the shafts and joints. Once you upgrade shafts and joints, the hp44's R&P and bigger carrier come into play.

I'd still limit a chromo'd hp44 at 37s for reliability under a full-bodied rig, but you'd likely never have a problem with it other than maybe an occassional hub depending on brand and driving style. I'd limit a 30 with chromoly shafts to 35s and expect to blow carriers and R&Ps if you're hard on it.

Jeeptech01
10-05-2010, 09:15 AM
Yea Im still on the fence about it. I may debate it a bit more in my build as time draws nearer. I dont want to whore up the TOTM anymore with my b/s though so it will be an easier read for those who want to reference it in the future.

SirFuego
10-05-2010, 10:41 AM
so you don't go pulling a SirFuego all over the place if you upgrade the shafts and joints, beefier Cs and knuckles, selectable hubs, better steering options, and bigger brakes. .

Heh. Still kept the stock C's, knuckles, brakes, and hubs on mine ;-) The only polishing it actually saw was the steering, truss, and shafts.

That said, I actually did a lot of research on HP30's and front Dana 44's before dropping the coin on my RCV's for the D30. Here was my logic for getting RCV shafts.
1) I knew 1 tons were in my future, but the finances weren't there.
2) I had a stock shaft failure take out the internals, so I was a bit biased against the thought of just stocking up on shafts and replacing them as they broke.
3) For every X stock shafts I would break, I figured that I would go through 1 ring and pinion with chromos. Eventually, a stock shaft/joint failure would probably take out a ball joint. I guessed X to be greater than 5. After seeing people around me cringe every time I would crank the wheel to full lock and bump it (without failure), I'd guess X was much greater than 5.
4) Chromos/CTMs were more expensive than RCVs. The extra couple hundred bucks of RCVs vs. chromos/stock ujoints was worth it to not worry about ball joint failure -- and I also figured the chance of needing to use a warranty was less. I figured the transferable warranty on RCVs really upped their resale value too. FWIW, after selling the RCV's, I'm out less than $250 from what I paid for them. I figured I would have lost about that much had I went with normal chromo shafts, too, so the cost is relative...

IMO, the only "problem" with running a polished 30 on 35s is that you NEED to let off the throttle when your front end is bound up or is in the air. On Little Jagger at Harlan, I had both front tires in the air a few times (at least it felt like it -- plus others had their tires in the air at the same spot), but I didn't have the balls to stay in the throttle. I didn't make the obstacle, but I didn't break anything either.

Where I went wrong was that I wasn't saving for 1 tons while I was wheeling my D30. I'm not complaining though because that money went to an engagement ring. After I broke my HP30 a few weeks ago (my front tires were in the air, but didn't let off the throttle), I figured it'd be best to just cut my losses and web wheel while I save for big boy axles.

I am still planning to "wheel" some wheeling events, but my "wheeling" is going to be on the couch while my gas money, registration fees, food money, etc goes into the bank. I might even "break" some stuff to while I'm "wheeling" so I can put more money in the bank while it gets "fixed". Speaking of which, when is GSSE-W? I'd like to "attend" this year -- hopefully even "break" something ;-)

JolleyRoger
10-05-2010, 11:20 AM
I probably got this from one of you...

Cody
10-05-2010, 12:48 PM
FWIW, On 35's in my current rig with warn's and CTM's in the 44 and Warn Premium hubs, I've only gone through 2 hubs in 2 years. I don't wheel this rig nearly as hard as my old rig, and the number of days on difficult trails is probably only a dozen a year at this point, so I think that is acceptable. Hubs don't bother me to change out on the trail.

I REALLY need to pull apart my CTM's and make sure they are in ok shape. A few of the zerks no longer allow grease in.

jsteves
10-05-2010, 12:59 PM
I have destroyed every hub I have put on my front 44 in less than two years.

2 Warn Prem
1 Warn standard
3 Superwinch

I swapped to the 44 b/c it was free and I liked the idea of selectable hubs. I will likely be putting in slugs...but like Cody said at least a hub swap is quick and easy.

Jeeptech01
10-05-2010, 01:44 PM
Selectable hubs is definitely an advantage of the 44 over the 30. I know you can put them on the 30 but IMO that would be a waste of money. IIRC the kit is like $800.

ajmorell
10-05-2010, 01:48 PM
Selectable hubs is definitely an advantage of the 44 over the 30. I know you can put them on the 30 but IMO that would be a waste of money. IIRC the kit is like $800.

Not to mention the cost of new wheels (the hub kit changes the bolt pattern)

Cody
10-05-2010, 02:47 PM
I'm not going to lie, I HATE getting in and out to select my hubs. This is a problem for me specifically because i have a front spool which makes it very difficult to steer. If I had an ARB and/or hydro assist (I'm ported, just no ram yet) I probably wouldn't disengage/engage my hubs 50 times per trail.

it usually runs fine
10-05-2010, 03:26 PM
Why do selectable hubs break so often? Do they hit stuff from sticking out. Is it just too much force for the smaller internals with a locker, gears and tires?

cowboy63b
10-05-2010, 04:07 PM
I have destroyed every hub I have put on my front 44 in less than two years.

2 Warn Prem
1 Warn standard
3 Superwinch

I swapped to the 44 b/c it was free and I liked the idea of selectable hubs. I will likely be putting in slugs...but like Cody said at least a hub swap is quick and easy.

try dynaloc they say unbreakable.

SirFuego
10-05-2010, 04:16 PM
Speaking of hubs, I saw the article in the latest Crawl Magazine regarding the Stage 8 locking spindle nuts. Is having the spindle nuts loosen up actually a common issue?

ATL ZJ
10-05-2010, 04:31 PM
Speaking of hubs, I saw the article in the latest Crawl Magazine regarding the Stage 8 locking spindle nuts. Is having the spindle nuts loosen up actually a common issue?

Not on mine... they were all tight after ~2 years when I checked them recently. That includes wedging tires and running into trees on accident. But I also know people who run the stage 8 stuff just as a precaution.

I would just replace the nuts and possibly the studs. The nuts are deformed thread IIRC, which lose a drastic percentage of their locking ability after just a few uses. I can dig up the numbers out of my NASA hardware guide if anyone is curious how much...

Cody
10-05-2010, 04:34 PM
try dynaloc they say unbreakable.

Is that the low-profile Dynatrac ones?

They are cool, and I would love for my hubs not to stick out so much, but in reality I would have to break an awful lot of lifetime warrantied Warn hubs for me to justify the cost of the Dynatrac ones.

AgitatedPancake
10-05-2010, 04:47 PM
Speaking of hubs, I saw the article in the latest Crawl Magazine regarding the Stage 8 locking spindle nuts. Is having the spindle nuts loosen up actually a common issue?

My 44 ones have come loose a few times, and when I pulled my friends 44 apart recently he had a loose one too. I can't vouch for his technique, but I actually do it in the manner they say, with overtorquing the primary nut first to set the bearings, then backing off a little, all while spinning the hub

jsteves
10-05-2010, 04:53 PM
Dynaloc appears to be for D60 only.

ELLLLLIOTTTTT
10-05-2010, 06:15 PM
Dynaloc appears to be for D60 only.

It doesn't matter. You have a special talent for destroying hubs. Might as well stock up on the cheap ones. :D

IndyZJ
10-05-2010, 06:39 PM
I would MUCH rather pop a hub than a joint, shaft, or something in the pumpkin. I consider them to be about the best thing to use as fuses in the drivetrain. Since something has to be the weak link, it might as well be easily replaceable and not necessary to the vehicle still being drivable. Lifetime warranties are nice, too, and you can pick up some factory parts to have as spares for next to nothing if your axle didn't come with them.

SirFuego
10-06-2010, 10:55 AM
OK I figured this would be a good time to get some input on my upcoming axle swap. Here are my thoughts so far (running some flavor of 37" tires FWIW)...

Front:
Known variables:
- Double ended full hydro (Overkill's old setup)
- 78-79 HP60. I don't have the tools or experience to safely burn on axle brackets, so I'm just sticking with the "cliche" front axle since it's easier for my buddy to setup. Plus I might be able to get one relatively cheap.
- 5.13 or 5.38 gears
- Hi-clearance brackets
- Sticking with stock shafts and knuckles for now, then upgrading later.

Undecided variables:
- Riddler/Crane diff cover or get it shaved to D44 clearance. The diff cover is obviously the easiest and cheapest solution and the "ramp" those covers offer should help the diff to slide over stuff a bit easier, but it would be sweet to have D44 clearance...
- Spool, detroit/grizzly, or ARB/Zip? If I find a good used ARB, I'm probably going that direction, but assuming my scrub radius isn't horrible and I'm running full hydro, can I really expect much advantage of a Detroit/Grizzly over a spool? I don't ever run my junk on the road, so I don't care about road characteristics.

rstrucks
10-06-2010, 11:20 AM
I really like having my ARB up front as I keep it unlocked unless I need it, but I wouldn't hesitate to run a Detroit either. IMHO I think a spool would put too much stress on the front shafts/joints and if you're running stock shafts for a while I'd skip it.

AgitatedPancake
10-06-2010, 11:32 AM
on dana 60 shafts I don't think you'd be stressing em out to be running spooled, but at the same time thats not the most appealing solution. I'm putting a detroit in my front axle - I'll get back to you with how satisfied I am with it haha!

The times I see a spool hurt most are when someone is trying to maneuver/rock CRAWL at low speeds and the spooled front end just pushes sideways off a rock they might be trying to get over while steering...but thats definately a combination of being locked front and rear

ATL ZJ
10-06-2010, 11:47 AM
Fuego, I run a spool up front and at times I like it. But I think ultimately I will have some sort of full case ratcheting locker like a detroit or a grizzly. I am very interested in the grizzly due to their claims that it won't break like detroits do when a shaft breaks, and their $2000 collateral damage warranty if breaks, through the end of this month. I think I'm gonna test the 14b version of the grizzly first and then maybe stick one in the front if I like it.

The front spool probably contributes a lot to tire wear, but here in the east, at least with full hydro and a lot of backspacing, I usually don't have issues with turning radius, unless I'm on a rare grippy rock or pavement. For the high speed stuff, I like how the spool quickly digs the rig back onto the track I point it in and seems to help prevent sideways slides. My main complaint with the front spool is the shock loads it transmits. It obviously has seen some serious shock loads, because a few months ago I checked my ring gear bolts and they had all backed off about 50 ft/lbs from when I set the gears a year and a half before. You could make the argument that a locker might ratchet or at least disengage for a split second during those types of high stresses are applied.

The testing videos I have seen on zip lockers makes them look like absolute junk compared to an ARB...

CrawlerReady
10-06-2010, 12:09 PM
I have a Detroit up front because I figured with me running Spicer u-joints on my D60, it would be best not to have a spool that would just be putting that much more stress on things. I love the Detroit in the front. However, if there Grizzly would've been out at the time, I would've gone with it most likely.

Hopefully it's much better than their Zip is compared to the ARB like Cam mentioned.

SirFuego
10-06-2010, 12:12 PM
The testing videos I have seen on zip lockers makes them look like absolute junk compared to an ARB...
Like this one?
http://www.youtube.com/watch?v=dyzyAVPTM8c (http://www.youtube.com/watch?v=dyzyAVPTM8c)

I know it's probably too expensive to do, but I would like to see them do it on at least two or three more trials to be honest. Supposedly the same shafts can vary quite a bit in their ultimate breaking strength, so I wonder if that is true for lockers. I also wonder if not having the other shaft engaged in the locker affects the strength of the locker. If they are able to get an ARB to break in that same lab test, that all of a sudden totally changes the story...

I'm not doubting the results of the test (or even claiming that ARB "fixed" the test -- which I'm sure didn't happen) to be honest, but I just wonder how repeatable those results would be with more trials.

I'm not doubting that the ARB is a stronger product either (it's been around and redesigned multiple times already), but a single trial like that doesn't convince me that an ARB is a better all-round product -- but it does at least make me feel the extra money spent on an ARB is worth it. I know that sounds a bit hypocritical, but something that's proven in the field (the Yukon lockers are too new to be "proven") and supported by (incomplete) lab tests is worth the extra $80 or so, IMO.

jsteves
10-06-2010, 12:29 PM
It doesn't matter. You have a special talent for destroying hubs. Might as well stock up on the cheap ones. :D

I have broken two at once twice now. So, I now carry 4 spare hubs. Checker in Moab replaces the broken ones on the spot, so the broken ones travel to Moab for free replacement.

SirFuego
10-06-2010, 12:32 PM
By the way, wikipedia has some excellent descriptions and animations of u-joints and cv joints:
http://en.wikipedia.org/wiki/Universal_joint
http://en.wikipedia.org/wiki/Constant-velocity_joint

geberhard
10-06-2010, 01:15 PM
"Polishing a turd", what about what can be done ona rear ZJ 44 to make it last longer with 33-34"tires?

ATL ZJ
10-06-2010, 01:37 PM
"Polishing a turd", what about what can be done ona rear ZJ 44 to make it last longer with 33-34"tires?

standard procedure is to cross drill the shafts and weld the carrier bearings.

it usually runs fine
10-06-2010, 02:59 PM
"Polishing a turd", what about what can be done ona rear ZJ 44 to make it last longer with 33-34"tires?
If you have to ask, I seriously doubt your pushing the limits of your axle.

IndyZJ
10-06-2010, 05:00 PM
standard procedure is to cross drill the shafts and weld the carrier bearings.

I did both and polished the aluminum inside and out. It makes it slide over stuff better and improves oiling. Best of all, nothing says bling like a polished diff.

Mtn WJ
10-06-2010, 06:39 PM
Are you saying you have a lot of bling and like having your diff polished?

it usually runs fine
10-06-2010, 06:44 PM
back on topic please. anyone have any good axle truss pics for a d44?

AgitatedPancake
10-06-2010, 07:22 PM
Here's my front axle when I was building it, 2x2x.250 wall truss, 1/2" thick pass side upper mount with a 3/16" gusset.

http://agitatedpancake.com/random/jeep/dscn3200.JPG


One of the many reasons aluminum housings are bad. It was worse when I finally got rid of it, actually wore to the very edge of that bolt hole
http://agitatedpancake.com/random/jeep/dscn3248.JPG

Jeeptech01
10-07-2010, 09:42 AM
"Polishing a turd", what about what can be done ona rear ZJ 44 to make it last longer with 33-34"tires?

Did you read this thread at all? Or did you just post up? Reread the thread and get back to us.


Ok guys I was looking at the 8.8 last night and contemplating trussing it. The tubes are already welded and it is ready to go in. I know Im gonna have to put bump pads on inboard of the leaf mounts for the bumpstops so I suppose I could integrate them into the truss. So most guys with the 8.8 and claytons have a truss but I figured it was for the link mounts not strength. What do you guys think? It will def see 35's and 300hp. Would it be a waste of time or should I do it?

ajmorell
10-07-2010, 10:34 AM
I don't think you'll have any issues with 300hp and 35s on the 8.8 even locked....it is pretty stout and I think grossly under-rated by most people (I'm not claiming 1 ton strength here but it's pretty stout). I would truss it, but I can't really comment on how to do it specifically.

ATL ZJ
10-07-2010, 10:42 AM
I don't think you'll have any issues with 300hp and 35s on the 8.8 even locked....it is pretty stout and I think grossly under-rated by most people (I'm not claiming 1 ton strength here but it's pretty stout). I would truss it, but I can't really comment on how to do it specifically.

I would add a truss that has more attachment/weld area at the axle side. Clayton's design is borderline even for link mounts with 300 snappy horses IMO.

rstrucks
10-07-2010, 10:43 AM
I would think you'll be ok - unless you plan on jumping it or wheelling it hard. From what you have said in the past, Florida doesn't offer a whole lot beyond mud and sand so the axle shouldn't be in for too rough a life.

You could alway do it and play it safe? If you have the axle out and you are working on it already, I'd probably go ahead and do it.

Kauzi Zj
10-07-2010, 10:48 AM
You could alway do it and play it safe? If you have the axle out and you are working on it already, I'd probably go ahead and do it.

The main thing ive learned through this thread, and conversations with Dave and Tyler is, if you have the axle out and your building it to put in, now is the time to do whatever you can to make it as stout as possible, better to do it now, even if its not needed, then to get it put together, and realize you need it...

Jeeptech01
10-07-2010, 11:13 AM
Thanks for the input guys. I suppose I can just do it on a while its out type mindset. I'll probably go with what I know and just build a truss like my 44a one only on the top of the axle this time.

As far as the sucky Fl wheelin goes, yea its a bit weak, but I hope to hit some trips up North with you guys. Maybe GSSE sometime in the future. Since the Buick is gone I should be able to do more in the sport now. Esp if my son really takes a liking to it.

ajmorell
10-07-2010, 11:17 AM
I would add a truss that has more attachment/weld area at the axle side. Clayton's design is borderline even for link mounts with 300 snappy horses IMO.

Cam I don't follow you. At the axle side as opposed to what?...

napajeep
10-07-2010, 11:33 AM
I think he means more contact/weld area than what Claytons provides. More like the MVC truss.

ajmorell
10-07-2010, 11:55 AM
I think he means more contact/weld area than what Claytons provides. More like the MVC truss.

Oh ok that makes sense. I wasn't sure if he was talking about what you said or if he meant that the truss should extend a certain length across the axle.

Jeeptech01
10-07-2010, 11:59 AM
I was thinking something like this.. Except more cooler!

http://www.ironrockoffroad.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=IROR&Product_Code=IR-XD44T

ed: Only problem is I'll either have to mock the axle up and weld the perches on then blow it all apart to truss. Or.. Build the truss once its in the rig. I could do it on the lift though so it probably wouldnt be too bad.

ATL ZJ
10-07-2010, 12:03 PM
Cam I don't follow you. At the axle side as opposed to what?...

At the axle tubes. Just trying to say that the attachment point is the most important part of a truss. More weld area is key because that is where the leverage is.

seems elementary but you would be surprised how many people have gotten that part wrong, myself included in that group.

Jeeptech01
10-07-2010, 12:10 PM
So you mean the weld area to the pumpkin is not as important as the weld area on the tubes. IE the tubes being tied together brings the strength not the tubes being tied into the pumpkin?

dp96zj
10-07-2010, 12:24 PM
This is an example of a poorly built truss, IMO.

http://store.topguncustomz.com/storefrontprofiles/DeluxeSFItemDetail.aspx?sid=1&sfid=134402&c=691255&i=243897602

http://www.jeepsunlimited.com/storyimages/Coilover/Coilover013.jpg

I think it was on NAXJA, but I've seen at least two guys crumple this truss like a tin can while wheeling. They mount the links on the inside of the truss, getting rid of a decent amount of material that would've made it more rigid. It's not tied into the pumpkin, and there's barely any lateral support.




Hmmmm, maybe trusses should be a TOTM :D

CrawlerReady
10-07-2010, 12:30 PM
This is an example of a poorly built truss, IMO.

http://store.topguncustomz.com/storefrontprofiles/DeluxeSFItemDetail.aspx?sid=1&sfid=134402&c=691255&i=243897602

http://www.jeepsunlimited.com/storyimages/Coilover/Coilover013.jpg

I think it was on NAXJA, but I've seen at least two guys crumple this truss like a tin can while wheeling. They mount the links on the inside of the truss, getting rid of a decent amount of material that would've made it more rigid. It's not tied into the pumpkin, and there's barely any lateral support.




Hmmmm, maybe trusses should be a TOTM :D

That is a Rock Krawler truss. Same truss I have and yep, it bent slightly in the middle right between the joints. Can't remember which way, but that was when it was on my D44. I swapped it to my 9" and then added a 3/8" thick piece of steel that I welded to the top of the pumpkin. Then I notched the truss out a bit more to slip further down the tubes of the 9" so I could have more welding area. It goes just below the halfway mark on of the axle tube. Haven't had any more issues since.

http://photos-a.ak.fbcdn.net/hphotos-ak-snc1/hs082.snc1/4553_504793690550_330900191_119424_3965488_n.jpg

ATL ZJ
10-07-2010, 12:54 PM
So you mean the weld area to the pumpkin is not as important as the weld area on the tubes. IE the tubes being tied together brings the strength not the tubes being tied into the pumpkin?

Ha, I should have kept my mouth shut. Didn't imagine it would be this confusing. Tying into the pumpkin helps too, if you can. Build the truss the full length of the tubes if possible.

All I meant to say is make sure that thing is never coming off.

Jeeptech01
10-07-2010, 12:59 PM
Gotcha :smiliefail:

IndyZJ
10-07-2010, 06:19 PM
Build the truss the full length of the tubes if possible.

This. What a lot of people think of as a "truss" such as the Clayton's and RK examples is just a glorified link mount or "bridge" if you will. That's not to say that it won't work for its intended purpose (if designed and built properly), but it isn't really a truss.

geberhard
10-08-2010, 09:10 PM
Did you read this thread at all? Or did you just post up? Reread the thread and get back to us.

Hehe my bad, I missed the reference on the 44A (saw you rpic and truss on the WJ, good job on the setup).


The reason I ask about polishing the 44 is I have bent\broke two 44’s on previous ZJ’s (both 96 limited V8), and at the time (early 2000’s dang) there was very little if any aftermarket. No issues on my old WJ, but the WJ was not as severely abused.

I have a 98 ZJ now (5.9), long arms, some other toys. The ZJ will start seeing more trail action in the near future, as my one ton Wrangler is kind od far from practical and comfort with little ones.

I am looking into improving the rear 44 some, or possibly improving it somewhat so I will get more life out of it, but at the same time am considering if it is worth spending the time and $$ on the axle or just start on a new axle for the rear on the side. The rig will be used for moderate trail usage, and the plans are to keep it low, 4.5 lift, 33-34”tires with some trimming.


So on to the questions:

-I can get an empty XJ 44 housing pretty cheap, form the ZJ 44 what can be ported over? The XJ housing is a bare bones housing, no internals, no brakes. Will gears, carrier, brakes easily move over?
-As far as brakes, the rig has ABS, and I would prefer to keep ABS on. Back to the question above, can the ABS components be moved over (not sure how the dial ring, etc will work on the XJ housing??



On to some tech to add:


Low pinion 30 – sucky axle

HP 30 slightly better, carry extra spare shafts even with 33’s, do not spend the $ on selectable hubs, ARB, chromos etc if your wheeling style and goal are to eventually run 35’s and harder trails.

44 front – I recommend the F258 78-79 for simplicity and perfect width for most rigs. The housing is extra beefy, the high pinion works and clears out well on most Jeeps, and if you can, keep the original selectable hubs. The axle is definitely a good axle up to 37”tires on light wheels. If you are adding to the rolling mass (heavy tires, H1 doubl beadlocks, etc) chromos are your friend. That said, I only had a small breakage on the outer shaft which was caused by a joint cup popping. To prevent that, I highly recommend tack welding the caps of your joints on pretty much any axle. If you are planning anything bigger than 35’s in your near future, do not waste your money on a 44. I have friends that have $3-4K on a dana 44 which they still manage to beat somehow and you get to appoint that it is hard to justify upgrading (I have been there)

8.8 axles – pretty much in line with Dana 44’s, if you are going 8.8 as mentioned get the Exploder 96 and up, slightly lighter, plu disc brakes. If you are running a Ford 8.8, you MUST weld the tubes to the housing. It is a matter of time until they come apart. We helped two guys with the same exact issue on the trail, one had bigger problems, the tube completely spun out (behind a Wrangler).

Dana 44 rear XJ – pretty sweet setup, easy to install, and clean perches and burning LC and UC mounts, etc. For the mounts, get the RE ones, we used Mad4wd last time and took a lot more massaging that we hoped.

Semi floaters – junk if you are going to spend your money on a big axle go full floater

Dana 60 and 14 bolt – Great axles for the harder stuff, are almost perfect stock. I have a softer spot for 14 bolts, so I lean towards them for simplicity on setup, and how cheap they are to get and build. Clearance on the 14 bolts can be arranged by some shaving. Plan on 38’s and up to justify a 14 bolt. As with the Ford 8.8 if you are not planning to add a truss, you MUST weld the tubes to the housing. The rosetta welds are crappy and will crack on the worst place at the worst time (ask me how I know).

Portals – I am surprised to not see more rigs running portals, but as they have benefits they have drawbacks. Some rigs need lift to the sky to clear up the portal pinions, so if you are going portals and can find a set of Volvos that is the way to go. Mercedes are nice but are a paint to fit on most rigs.

Deuces. You kidding? On a unit-body… hmm no… sure you can but why?

geberhard
10-08-2010, 09:16 PM
Some links that may help:

detroit locker easy install at home:

click here for link for Detroit install (http://www.pirate4x4.com/forum/showthread.php?t=328610)

http://img.photobucket.com/albums/v256/geberhard/IMGP5263_500.jpg

http://img.photobucket.com/albums/v256/geberhard/jeep%20projects/dana%2060/1finished.jpg

Newbie built front 60 (http://www.pirate4x4.com/forum/showthread.php?t=334736&page=5)

14 bolt rosetta welds cracked:

http://i195.photobucket.com/albums/z236/crosscountry4x4/Rubicon%20-%20June%202007/Gui/IMGP9946.jpg

http://i195.photobucket.com/albums/z236/crosscountry4x4/Rubicon%20-%20June%202007/Gui/IMGP9947.jpg
fixxed :D

http://img.photobucket.com/albums/v256/geberhard/jeep%20projects/14%20disc%20convo/IMGP0874.jpg

SirFuego
10-13-2010, 04:18 PM
So about 35 spline drive flanges...

Some are made of chromoly. Some are made of 300M. Some are made of "the same type of metal used in ring and pinions". It seems that basically every manufacturer out there makes them. Does the material really matter? Or is this something that isn't commonly broken regardless of the type purchased?

ATL ZJ
10-13-2010, 04:51 PM
So about 35 spline drive flanges...

Some are made of chromoly. Some are made of 300M. Some are made of "the same type of metal used in ring and pinions". It seems that basically every manufacturer out there makes them. Does the material really matter? Or is this something that isn't commonly broken regardless of the type purchased?

Guys with sticky 39s+ and significant horsepower will occasionally strip one out. Mine are warns and they aren't anything special at all... and they are one of the ones I've heard of stripping out the most. In most cases you are going to break a 35 spline 4340 shaft before the drive flange goes. I'm tempted to grab a set from ECGS and keep my Warns for spares. You on the other hand should be fine if your plan is to keep the 5.2 and run a smaller tire.

SirFuego
10-13-2010, 05:01 PM
Yeah, definitely no immediate plans for anything beyond 37s and the 5.2. Even if I blow out the 5.2, I'll probably just swap another one in. I've been through some pretty drastic changes in the past couple years and I want to get my rig more "stable" to where I'm not constantly upgrading and fixing major stuff. Given the lack of body panels and decent approach/departure angles, I don't think I even came close to the potential of what my rig could do on 35s due to the weak front axle (for what I was trying). I don't want to go too big this time around because I really hope to stay on 37s for a while, which should allow me to try a lot more than I did before without as much of a concern for catastrophic breakage (though I'm sure I'll go through a shaft/joint or two before upgrading to 35 spline). I wouldn't mind staying on 35s to be honest, but I think that I would take too much of a hit in the ground clearance department. But I digress...

geberhard
10-13-2010, 08:55 PM
As far as flanges, as mentioned most likely you will brake shafts and joints first. I run a set on my old rig for some time (tralered), but was not pleased with having to po in and out for street driving (run a square d shaft front). The rock and roll offroad ones are pimp, and the Warn as mentioned are known to strip or crack, but warranty. I went back to Warn manual lockouts and as they are premium with lifetime just used warranty when needed (have an extra for trail spare usage).

You cna get lucky and find an old Spicer OEM 30 spline, rebroach (about $50-80 to respline from 30 to 35) and is arguably stronger than the aftermarket manual hubs.

I think for a 42"and below medium weight wheel tire combo - i.e. Irok with H1's having hubs or flanges that break are a better fuse than axles and internals snapping, and a quick fix on the trail.

zjeepin
10-14-2010, 11:44 AM
I run stock spicer d70 flanges with no issue to this point..FWIW.. I ran stock hubs before I upgraded to 35spl outers and I constantly bashed them on rocks and the dials quit working so I may as well have had drive flanges.

geberhard
10-14-2010, 02:16 PM
sweet d70 seem pretty hard to find. as far as bashing your dials, are you running wheels like non reentered H1's to bash teh dial on teh rocks? Mine are pretty much in line with the wheel lip, so mostly protected.

For those running 44's in the front, a quick and cheap tip is to run Waggy flanges on teh front, I had them as a spare alternative to hubs and used on the trail. They are pretty solid and seemed bulletproof for a 44 (full engagement), plus are plentiful on junkyards. I remember paying $5 for 3 sets :) They pop right in. You will break a stock shaft before breaking the waggy flange, plus you cna carry a couple spares rather than a full spare manual hub.

it usually runs fine
10-14-2010, 11:48 PM
sweet d70 seem pretty hard to find. as far as bashing your dials, are you running wheels like non reentered H1's to bash teh dial on teh rocks? Mine are pretty much in line with the wheel lip, so mostly protected.

For those running 44's in the front, a quick and cheap tip is to run Waggy flanges on teh front, I had them as a spare alternative to hubs and used on the trail. They are pretty solid and seemed bulletproof for a 44 (full engagement), plus are plentiful on junkyards. I remember paying $5 for 3 sets :) They pop right in. You will break a stock shaft before breaking the waggy flange, plus you cna carry a couple spares rather than a full spare manual hub.
cool mail me a set

geberhard
10-15-2010, 03:02 PM
Ah, have not had a 44 in a while, but will check my parts pile, may have a coupel sets still laying around.

Kinda hard to see but it is basically the part that goes under part 18 on the diagram below. I tried searching online for a pic of the flange\hub part but no luck. It is basically a two piece flange assembly that goes on the front on non manual hub FSJ.

http://www.jeep4x4center.com/jeep-brake-parts/images/62-91-cherokee-sj-brake-parts.gif

fredr1980
10-15-2010, 07:28 PM
You cna get lucky and find an old Spicer OEM 30 spline, rebroach (about $50-80 to respline from 30 to 35) and is arguably stronger than the aftermarket manual hubs.

Speaking of hubs I just started a 1-ton build on my wife's CJ and the D60 I picked up didn't come with outer stubs or locking hubs. I've actually been thinking picking up some oem Spicer 35-spline outers and reproaching some old spicers locking hubs as the design seems to be the same concept with regards to the "locking cogs" as the high end $500 Dyna track hubs from what I read on pirate. I think I found some spicers locally on craigslist but I'm not sure of these are it or some just some cheap hubs. I've done searches on google and on pirate but couldn't find definitive pictures of what they D60 spicers look like, I know that the D44 spicers had blue dials but do the D60's also have blue dials or are they red like below, can someone confirm that they look like one the picture below.

Thanks again,
Fred R.

http://inlinethumb14.webshots.com/47885/1435988233077117139S500x500Q85.jpg (http://good-times.webshots.com/photo/1435988233077117139VDXUam)

geberhard
10-15-2010, 07:48 PM
Fred, I will dig though my pics. Those look like stock spicers to me.

http://img.photobucket.com/albums/v256/geberhard/jeep%20projects/dana%2060/60beauty.jpg

pics from them disassembled here (not mine, but mine were exact the same):

http://4x4.forensick.net/88bronco/images/dana60/05.jpg

...and this is the 'gear' that gets broached. MUCH beefier than the crap inside Warn's hubs.
http://4x4.forensick.net/88bronco/images/dana60/08.jpg

MADMAC on pirate broaches them If not mistake was about $50 AFAIK...

They are extremelly well designed, and you can find them cheap. I sold a set with outer 30 splines for almost nothing, wish I had kept them :D

fredr1980
10-15-2010, 07:55 PM
Fred, I will dig though my pics. Those look like stock spicers to me.
MADMAC on pirate broaches them If not mistake was about $50 AFAIK...

They are extremelly well designed, and you can find them cheap. I sold a set with outer 30 splines for almost nothing, wish I had kept them :D

Gui,
Thanks, I'll hop on these then :mrgreen: should be under $100 after all said and done with getting them broached to 35-spines.

Thanks again,
Fred R.

geberhard
10-15-2010, 08:21 PM
Cool, use teh second pic for reference, good isdea to po em up and see first just in case anything is chewed up and they have not been replaced for some other internals. Good luck! $100 for the set broached is a sweet deal!

Kauzi Zj
10-16-2010, 04:24 PM
Ok what is the general consensus on buying a brand new Rubicon Front D44? again im running a 94 ZJ 5.2 and will be running 35's....Im asking because I might be getting a smoking deal...still have to see

Jeeptech01
10-16-2010, 04:49 PM
You could buy the matching rear from me.

geberhard
10-18-2010, 02:41 PM
If you are getting a smoking deal, the Rubi 44 is a hard to pass option, pretty much bolt on, marginally stronger than a 30, geared and locked. I woudl not have a problem running one :)

ajmorell
10-18-2010, 02:59 PM
Ok what is the general consensus on buying a brand new Rubicon Front D44? again im running a 94 ZJ 5.2 and will be running 35's....Im asking because I might be getting a smoking deal...still have to see

It would have to be a real good deal, but they are a worthwhile upgrade. What are you planning to do to address the difference in bolt patterns?

geberhard
10-18-2010, 03:18 PM
I did it the other way on an old TJ, (Rubi rear axle and spacers front). Spacers in the front, never had any issues. If I coudl find a deal on a set of Rubi axles why not run them?

Kauzi Zj
10-18-2010, 06:01 PM
It would have to be a real good deal, but they are a worthwhile upgrade. What are you planning to do to address the difference in bolt patterns?


It is, less than it would cost me to build my 30, and I was thinking a 9 inch rear...

Jrgunn5150
10-19-2010, 05:42 PM
I hope you guy's can shed some light on something I came acrossed today.

Guy on NAGCA was using Reid knuckles on a HP 30 with Waggy spindles, mated a Waggy outer to the 30 inner with a 297 joint. By doing this he got rid of the unit bearing and picked up real lockouts. It made for a 6 lug pattern, but Chebby wheels are common and cheap, or he could have used a Furd spindle for 5 on 5.5.

This got me thinking about doing the same to my WJ using Waggy 30 inners since the overall width is very close. That would allow me to ditch the cv shafts also, and be alot cheaper than any other option.

Am I missing anything here? It seems like a great option if I'm not, my own WJ will never get over 33s on it.

geberhard
10-19-2010, 05:54 PM
Search for D30-44 hybrids here and on pirate, a lot has been covered before. IMO not worth the money unless you already have sunken money on your 30 (ARB and gears). You can build a simpler D44 front with a Waggy donor and use of the shelf parts. If it were me I would look into a pair of Waggy 44's.

Jrgunn5150
10-19-2010, 06:00 PM
The correct search term helps a ton lmao thanks! I've been lookin fruitlessly all day.

I totally agree that a Waggy axle or HP44 would be better, but I'm working on jackstands outside with hand tools, so for me a bolt/drill/grind option is worth alot.

Jrgunn5150
10-19-2010, 06:42 PM
Ok, now that I'm home on a real computer, I can see, that the 30/44 option blows. It's either4 just as much work or just as much money as a axle swap.

geberhard
10-19-2010, 08:30 PM
Personally a JK swap if you can find a good deal will be a simpler swap, but the waggy 44's are stronger in stock form, plus a lot of benefits, manual hubs, easy off the shelf and junk yard parts etc. I would start building the set on the side if you have the space and time. Pick and pull normally has the waggies in this area (CA Bay Area) for about $100 a pop or less on half off days.

I am also debating on what to do on the ZJ axle build wise, but am possibly going to wait and kill the current ones first :)

ATL ZJ
11-29-2010, 02:26 PM
Chad, did you ever finish this? I popped a yukon this weekend and would like to use your spreadsheet to guide my decision of what to replace it with...

http://imgur.com/XLMIr.jpg

AgitatedPancake
11-29-2010, 02:43 PM
Damn, superior imports have pretty big numbers...twist and torque!

ATL ZJ
11-30-2010, 04:09 PM
OK, so I might be talking to myself here, but I have an engineering/metalurgy question. I may have already asked this some time ago but I don't remember the answer if I did.

Let's say you run a stub shaft on one side of the rig for two years (we'll say driver). You use it hard and then you pull it.

If you reinstall it on the other (passenger) side, is it more likely to break because it's being twisted in the other direction? Or does the stub remain equally as strong, as long as it hasn't reached yield and experienced plastic deformation? Do the grains in the shaft develop a memory or do they remain indifferent to which direction they're being twisted as long as the twisting is still within the shaft's range of elasticity?

BigClay
11-30-2010, 04:41 PM
^ wow, my head hurts now :D

zjeepin
11-30-2010, 04:49 PM
i like the thought process cam... Paging Paul.. downtowncb..

my thinking would be to picture the shaft as any load bearing object, with its ultimate load and yield strenghts.. the more times you approach or reach the yield the likelihood of it breaking increases.. when you're trying to break something by fatiguing it, it become easier to cycle back and forth in both directions the more you cycle it..

if you consider work-hardnening, the shaft would be stronger if left in the same position experiencing the same loads.. my .02..

downtowncb
11-30-2010, 05:59 PM
First I think there are a bit too many variables to say for certain. In a general case say the shaft was used hard for years but we know for certain that it hasn't endured any plastic deformation (twisted splines, necking, etc.). For fatigue analysis of a shaft subject to the random "complex" loading during it's normal use, the loading would be reduced to a simple cyclic loading based on the peak loads. Because of this I believe the shaft would be equally likely or unlikely to fail in either direction after it's initial use.

Under an axle shaft's normal operating conditions there should be no work hardening. Work hardening requires some small plastic deformation to occur. For example, bending a paperclip. If you bend it one way and try to bend it back the opposite way, it will bend separately next to the first bend. This is caused by work hardening of the grain structure in the wire. The most likely place for work hardening to occur on an outer shaft would be right after the splines exit the hub. If it were enough to be readily visible, I would consider replacing it or at least carrying a spare.

ATL ZJ
11-30-2010, 11:46 PM
Wow, that's an awesome explanation and the paper clip analogy seems logical...

Here's the shaft that broke. You can see it snapped right where the splines end. The root of the splines was the smallest diameter part of the shaft, instead of having the main body of the shaft neck down from the splines like properly shaped shafts do (14b shaft for example). Interestingly enough, the line I drew down the body of the shaft when it was new was still on there, and it was still 100% straight, showing no plastic deformation past the weakest point of the shaft where it broke.

http://img.photobucket.com/albums/v125/atlzj/IMG_0852.jpg

This is a real world example of how smaller diameter shafts (and their generally higher deflection characteristics) are actually tougher, even though it may seem backwards at first. The shaft that necks down is capable of absorbing more torque so the rest of the assembly may never see the higher ultimate torque numbers that a larger diameter shaft might transmit.

But... if any of you other engineers have a different theory on whether a stub is weaker when flipped, please chime in... I have one spare and it has been run on the driver side already.

ATL ZJ
12-02-2010, 10:12 PM
First I think there are a bit too many variables to say for certain. In a general case say the shaft was used hard for years but we know for certain that it hasn't endured any plastic deformation (twisted splines, necking, etc.). For fatigue analysis of a shaft subject to the random "complex" loading during it's normal use, the loading would be reduced to a simple cyclic loading based on the peak loads. Because of this I believe the shaft would be equally likely or unlikely to fail in either direction after it's initial use.

Under an axle shaft's normal operating conditions there should be no work hardening. Work hardening requires some small plastic deformation to occur. For example, bending a paperclip. If you bend it one way and try to bend it back the opposite way, it will bend separately next to the first bend. This is caused by work hardening of the grain structure in the wire. The most likely place for work hardening to occur on an outer shaft would be right after the splines exit the hub. If it were enough to be readily visible, I would consider replacing it or at least carrying a spare.

OK, I've obviously been dwelling on this too much. But it's really interesting and the decision to run a used stub in a new direction could theoretically ruin a weekend...

I also came across this- do you think it applies in this situation? http://en.wikipedia.org/wiki/Bauschinger_effect

and where the F is Paul?

Jeeptech01
12-04-2010, 01:01 PM
My totally pedestrian view on the subject is running a shaft backwards should be given no more thought that throwing your rig in reverse on the trail. Sure you dont use reverse as much as the forward gears but the ratio is also steeper. My .02

ATL ZJ
12-04-2010, 02:05 PM
My totally pedestrian view on the subject is running a shaft backwards should be given no more thought that throwing your rig in reverse on the trail. Sure you dont use reverse as much as the forward gears but the ratio is also steeper. My .02

That's partly true, and front 44 shafts especially have been known to fail when bound up, backing up. But the difference I see is the percentage of the time you're loading the shaft in forward vs. reverse... sure it will see stress in both directions but how often are you absolutely hammering on it in reverse? rarely...

Jeeptech01
12-04-2010, 03:13 PM
Hrm. Yea I figured it may relate more to the amount of time it is being used vs one hard use but I thought the paperclip description negated that line of thought.

I understood it as one beastly twist killed a shaft not the thousands of small and medium twists slowly aging the shaft until its failure.

Admittedly Im not too "up" on this type of thing but wanted to offer a different.. less intellectual line of thought LOL.

ATL ZJ
01-18-2011, 11:47 PM
Well, my replacement yukon 35 spline inners came today. Which was cool in its own right because I now have two new, spare 4340 inners. But the reason I'm posting is because the short side inner is different than the one I had before.

Instead of maintaining a constant outer diameter like the one I twisted, this one has proper neckdown from the splines and a smaller operating diameter. I'm still going to run the shortside ten factory inner I have been, and hopefully I won't need to ever test the yukon, but it's good to see them change their design for the better. Figured I should correct what I said earlier. Not sure if they changed their long side shafts though- the new one I got is the same as the one I broke.

SirFuego
04-13-2011, 03:11 PM
Extra pinion supports like in the 14b minimize ring and pinion deflection
Here is an interesting thread that popped up on Pirate recently. Even though it's obviously an advertisement for Currie, there is some interesting discussion cropping up regarding whether the extra pinion support really is why the 14bolt is "stronger". The theory (made by Currie and some other folks in the thread with a lot more experience than me), is that carrier deflection is usually the problem and not pinion deflection. The major advantage of the 14 bolt is due to the size of the carrier and not necessarily the 3rd pinion bearing (which probably does still make it stronger, but perhaps not really giving it much of an advantage if the pinion really doesn't deflect as is claimed).
http://www.pirate4x4.com/forum/showthread.php?p=12772027#post12772027

ATL ZJ
04-13-2011, 05:13 PM
Interesting but I think the key thing to remember about the 14b is that it just works. Out on the trail, who cares what the reason is, whether it's the pinion support or big carrier. The price/reliability ratio is unbeatable. And shaved it's gonna have almost as much clearance as that $2k center. /devilsadvocate

SirFuego
04-13-2011, 06:03 PM
Yeah I didn't want to imply otherwise. The 14B is a great axle -- especially when it's shaven. Just found it interesting about the findings about the pinion support.