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zjdude94
06-28-2004, 01:21 PM
:?: what kind of mechanical know how do you have to know how to balance driveshafts or should i just get a custom set altrnatives thanximg][/img]

Bulldog 6
06-28-2004, 01:50 PM
Balancing a d-shaft is like balancing a wheel, you need the machine to get it totally right. Any driveline shop that makes their own or rebuilds yours will have the machine to spin it and tell them where to add the weight.

They should do a final spin to verify the weight is correct.

Now just because they can make their own does not mean it is right. In college I worked at a driveline shop. They brought one in for rebuild that was almost new. Very good construction and very good looking welds. The yolk end came off because the original shop that built it put the weld all on the pipe and had no penetration into the yolk. He was an out of town trucker and could not get it back to the first shop, he bought one of ours and was back on the road.

zjdude94
06-28-2004, 01:55 PM
thanx got the 231 havin issues where you at in IN

Bulldog 6
06-28-2004, 03:06 PM
I live in Valpo. Right now stationed with the Army in Ft Wayne until end of the year. Got called up for Homeland Security. It was this or Iraq. I'll go do what I am told where the Army is concerned but if I have a choice, it's the same pay here or there and I am not getting shot at here.

It was origianlly just for 1 year but turned into 2 years.

BigDaveZJ
06-28-2004, 03:10 PM
thanx got the 231 havin issues where you at in IN

I think the real question here is what are the underlying issues that make you believe it's your driveshaft being out of balance? I take it you swapped it in? Did it work fine before?

Bulldog 6
06-28-2004, 03:24 PM
thanx got the 231 havin issues

The FAQ has a writeup about swapping in the 231. It mentions using an SYE to eliminate drivetrain vibes and adding strength. Somethin to ponder if you have not gone down that road yet.

Depending on how much lift you might need a t-case lowering kit as well.

BigDaveZJ
06-28-2004, 03:33 PM
Depending on how much lift you might need a t-case lowering kit as well.

Way to give the JU answer!! T-case lowering kits are basically a joke on ZJ's. Plenty of people are in the 6"+ range of lift without needing a lowering kit or an SYE. Yeah lowering kits are cheap, but you're just putting additional strain on the front shaft by doing that.

Alaska ZJ
06-28-2004, 03:39 PM
Alright this is the sort of stuff I have been wanting for a long time. Pirate is way big most of the time to explore this stuff.

Well here is some driveline tech from a friend of my Bgreen. Brook is an outstanding machinist and dedicated 4x4 enthusiast.

Bgreens Driveshaft page (http://www.akfabshop.com/alaskaoffroad/driveshafts.htm)

If your looking for a trail shaft on a buggy. It is not really that critical that it balance and you need TONS of slip usually. Reciever tubing can give you both. Yes I said square driveshaft on a drail rig. Heck if you have hubs in the front I would do it on a street rig.

For a daily driver you can do this. Install your yokes onto the diff and Tcase.

Install the DOM tubing that you intend to use and that correlates with your yokes. If you are putting in a mid shaft slip make sure everything is measured up so that compression doesn't bottom the shaft and extension does not seperate it.

Then once it is all installed put your runnout dial (same dial that you use to measure backlash when setting gears) on the framerail with the magnetic base. Set the dial to read all the way around the shaft.

Simply tap it with a hammer until it is true to your liking. Repeat in several places along the shaft.

When satisfied simply tack it in place in 3 locations. If you unsure you might want to check with the runnot guage again.

Personally I would pull it down and weld it on a bench but I guess you could do it on the truck (would ruin seals and such though most likely)

Weld it all up. Now here comes the tricky part. Take it to a driveshaft shop and have them balance it. Usually cost's me about 10 bucks for them to spin it up.

All in all you will probably save about 75 bucks. For some it is worth it, others not.

All my advice assumes you know how to weld and that your fairly mechanically inclined.

And because threads without pictures suck.

1350 v 1410 yoke

http://www.akfabshop.com/alaskaoffroad/images/Tech/Driveshafts/1410vs1350_205_2.JPG

zjdude94
06-28-2004, 04:05 PM
whoo hoo thanks for all the input took it to friends shop reg driveshaft guy out found frozen jt 4.5 right now so sye not nec. ive been eavsdropping for over a year and am always amazed at the technical output NAGCA basicaly you guys thanks

Kraqa
06-28-2004, 08:05 PM
ya seen a few rigs with squar drive shafts. definatly something i'm going to do. gotta finish up the details involved with my axle swap right now. lotza little things.

nmzj
06-28-2004, 09:14 PM
For something not to precise, a hose clamp will work. Tighten it down, go for a drive. If the vibe is worse, loosen and turn a little. If it gets worse, you went the wrong way. If it gets better, keep going until it's tuned.

As for the reciever tubing...so getto you got to love it. I've seen it and plan to try it sometime... :D

Jason

Alaska ZJ
07-03-2004, 09:07 AM
Picture?

http://www.wheelingadventures.com/Northern4x4/iB_html/uploads/post-2-38711-indicate_shaft02.jpg

I have a good buddy that makes drivelines for a living. He is also Jewish and would rather do it himself most of the time. Any and all question from this thread will be run through him as well, just for a sanity check.

chopshop
07-03-2004, 03:09 PM
I think about .010" runout is good enough. you might get better that that at first, but welding will blow it out some.

nate
07-03-2004, 06:00 PM
For a trail rig, 0.010 runnout woould be ok.
For the street, it will probably vibrate. 0.003 is usually the max runout you can have. That is directly from the guy who both Nate379 and Alasak ZJ know who build these for a living

I got my rear driveline built at 6 States in Anchorage. Vibrated right from the start. Brought it back several times... no nothing wrong, must be your Jeep, just deal with it. Even brought it to another driveline shop and asked them to check the runout. Nope, it's fine.

Well back to 6 States. I told them either made this thing work, or your building me a new one for free. I didn't pay $250 for a piece of pipe that makes my Jeep feel like a washing machine on the spin cycle.

Manager all of a sudden got all nice... Oh, I'm sorry about this sir, do you want a soda? something to eat maybe? Here have a seat, it should only be a few more minutes, etc. Funny as shit.

Back on the balancer... check the runout. 0.022 out! They had to cut the yoke off and reweld it on there straight.

note to Nate- just wanted to update that information from BJ and Frosty man. They have the practical experrience and the training to make those runout specs more legit than just you or I would by repeating them.