swapping axles in a WJ and keeping the speedo

[BigDaveZJ]

So after Keith grenaded his 35, we were talking about how to make another axle work. Apparently the WJ picks up its speedo signal from the ABS tone rings. Obviously new tone rings could be machined into a new axle, but holy $$$!!! Sooooo, has anybody tried, or have the means to try and see if the t-case style speedo system would work with the WJ's computers or any other ideas on how to make it all work???

We spent some time brainstorming and thought of a couple ideas

t-case speedo
re-wiring the rear sensors up front and "trick" the computer into thinking there is rear sensors
simply cut the rear ones off and see if it will work off the front

[Halfdoc]

I wish the pictures were still there but I am sure he has them somewhere:

http://65.42.106.152/forums/showthread.php?t=456577

Definately possible to use the TC for speedo input.

Good luck.

David.

[BigDaveZJ]

Hmmmm, so now we just need some spare 242 parts to see if this would actually work on Keith's WJ. Not to mention needing to get his rig back from Moab!! Sounds like a relatively easy wiring job. It MIGHT even be possible to keep the ABS too if someone wanted.

Great find on that thread!


And just in case the hamster croaks at JU here's what ALWJ said in the thread:

--------------------------------------------------------------------------------

After staring long enough at the WJ wiring diagram I was able to determine what wires needed to go where. Just took it for a test spin and everything works (except I have the wrong size speedo gear). I plan to write a more detailed writeup after about 500 miles to make sure everything is cherry.

First off let me explain how the speed signal works in the stock system. Tone rings on the rear axleshaft are used to send pulses which are sent to the Antilock brake control box. (The FSM calls it the CAB) In the CAB the signal is split and the speed signal is sent to the powertrain control module (PCM). The white wire with an orange stripe coming out of the CAB is the magic wire carrying the speed signal.



The new speed signal will have to be spliced in here so that the signal goes TO the PCM. The signal I used came off of a 231 transfer case with a speedometer adapter and harness for a TJ (I'm pretty sure this unit is the same for all TC's and model Jeeps)


The white wire with the orange stripe from the speed sensor needs to be spliced to the white wire with the orange stripe going to the PCM (coincidence? I think not)

The solid orange wire on the speed sensor is for a 5V power supply. I found several 5V supply's in the power seat sensors and was going to tap them for power, but a friend made up a circuit for me that converted 12V to 5V (Thanks a bunch Mike!) so I didn't have to fiddle around with tapping the seat. I'm sure he wouldn't mind making a few for people who want them. Just e-mail me if you're interested and I'll see how much he wants for one.

So that's the secret. I know I'm not the first to do this. Off the top of my head Anton, Rizzo, and Henley have all used this method, but if you ever bothered to ask them or call their shops you'd get the run around. I remember the shop that did henley's setup said it was intellectual property I must say that Anton was actually very helpful and he helped me quite a bit, but he wasn't exactly sure which wires went where which left the rest of the puzzle up to me. I can understand he's a busy man

[chadjans]

I have a spare 242 in my garage now...

Chad

[ATL ZJ]

I also have a 242 that is only good for spare parts sitting in my garage.

[JohnBoulderCO]

t-case speedo
re-wiring the rear sensors up front and "trick" the computer into thinking there is rear sensors
simply cut the rear ones off and see if it will work off the front

I traded e-mail with Keith while on travel last week.

1) Yes, but you need to swap the T-case, WJ cases do not have the speed output.
2) Yes that would work and you would still have ABS off the front tires, all four wheels would pulse when one front slips. The easiest solution and one that I have considered. Need to make sure the tone ring notch count is the same between the front and rear. The WJ rears are 48. The ZJ rears are 54.
3) Don't think it will work. You could unplug the rear ABS wires and drive around for a while to check. If not, then back to #2.

4) Use the tone ring off an 8.8 and a Truspeed to correct the speed pulses (the 8.8 single tone ring has 108 notches) and send it to the speed input as indicated in the article in the above post. No ABS but you have speed control for the computer.

I am going the route of putting WJ tone rings on the 8.8 shafts. Tom Z did it for the ZJ, so it should work for the WJ.

BTW, I think I bent a D44A shaft at GSW. I had a wicked vibe driving home. Either that or I knocked the weights off my new Tom Wood's rear shaft. I put it in just before GSW, since the factory one was bent and giving me made vibs. I will pull the shafts next week and if one is bent, I will start my 8.8 swap and pass along what I learn.

John

[Mtn WJ]

Funny thing. I was going to post some questions based on Johns and My emails last week. I was out of communication range for a bit taking my son to cub scout camp last weekend. Thanks for looking out for us guys.

These are my thoughts so far and they apply to me a little different than John becuase he is running steelies with less back space than my stock rims and using spacers. Chime in as you please or please chime in as you will.


Ford Explorer 8.8
Tone ring on ring gear has 108 notches and WJ's have 48 so removing every other notch will get you close but you will need a 250.oo true speed and you will not get ABS unless you wire them all together and will only have 3 channel ABS.. Supposedly they have same type of sensors otherwise it will be a PIA to put the WJ sensor on the diff housing.

Tom has a great method that requires machining and grinding to put the WJ's tone rings on the ends of the axles similar to the WJ's set up.

ABS is not a priority but it would be cool do have it all.

The 8.8 is 59.4 inches wide and the WJ axles are 63 and some change. This means spacers are needed and for me it would be 3.5 per side or get new rims and put 2 inch spacers in rear.

The 8.8 does come with Discs and 4.10s which I have and will not need to re-gear.


Isuzu Rodeo Iron D44 Yep its a real D44.

These have the tone rings on the axle shafts similar to a WJ. I have yet to look at one in person do to the donor's owner being on vacation.

I want to see it in person to determine if I can machine my stock rings to work

The Rodeo was originally a 4 link with coils and shocks in similar mount locations. It may be a little less fab work but with either axle I will need to fab up a mount for the tri-link a frame above the diff.

The Rodeo D44 comes stock with 4.10s again good for me because I have re-geared to 4.10s already.

Rodeo is 63 inches and some change but has 6 bolt lug. I found one-piece spacers that convert 6 to 5 lugs but cost apx 100 each. This way I can re-use my prefered stock rims.

The Rodeo 44 has been known to hold up to 35's like the 8.8 and some claim 37's. I do not plan to be bigger than 33's and likely will stay with my 32's.


Both Axles. I will be able to double check this theory when I get my Jeep back home on Saturday but It seems from memory that the front tone rings have the same number of notches and are the same diameter. This means we can pull the ABS fuse and use the front rings for Speedo by re-wiring the speedo sensor wires to the front sensors or swap the senors from the rear to the front.

Again I want to have both work but giving up ABS will not be the end of the world.

I have read about the method posted by ALWJ and it may work out ok but I would like to keep 4 wheel ABS and would prefer not to swap tcases. Yes the WJ 242 has several differences than other 242's including external shaft lengths etc. I suppose it would be worth doing that when doing a SYE and bunch of other pricey things all at once.

How about your thoughts and concerns. I am trying to be done by the end of July to allow some wheeling this summer.

Thanks again guys. Keith S

[ELLLLLIOTTTTT]

why not use a 9"?

[JohnBoulderCO]

why not use a 9"?

Yeah Keith! How about a D60 or a D70 or an Unimog 404 portal, or a .......

[Mtn WJ]

I have thought about a 9 inch too but do not have one to look at to decide if the tone rings will be possible to install on it. As far as I know there have not been a lot of 9 inch Fords with ABS. It does not mean a method could not be developed to put them on similar to the 8.8 but I have no idea. I like that the housing is steel instead of cast which will make welding on some kind of upper bracket for the tri link easier and they come in more widths than anything else I know of.

Yea John I was thinking of Rockwells myself.

[Mtn WJ]

Here is another question.

The WJ axles shafts are slightly longer on one side than the other. I do not know yet until I look and measure the 8.8 or the Rodeo 44 if they are off set the same way or centered.

However it would not surprise me if they are centered or the off set is different than the WJ.

My question is since I will need to put on spacers would it be a good idea to mount the spring and control arm brackets off set to make the pinion yoke in line with the dshaft and then adjust the difference with 2 different width spacers? I do not see any reason this will be a bad idea but what are some of your thoughts.

The difference is around a half inch if I recall correctly so it may not matter anyway.

Keith

[BigDaveZJ]

Keith,
The 8.8 is offset a bit to the pass side I think and I welded the brackets on centered on the tubes. No issues with the increased angles on the driveshaft. Running different size spacers would be a last resort IMO.

[Mtn WJ]

Yea I am thinking the same thing. I am engineering a bit vicariously since my Jeep is still in Moab.

John just emailed me after counting the notches on the front tone rings and they are the same count as the rear which makes using them for the speedo a good back up plan if we are unable to have a full solution in the rear.

Keith

[SLO MO]

1) Yes, but you need to swap the T-case, WJ cases do not have the speed output.

Actually all you need to do is swap the main shaft for one that has the "worm" for the speedo gear and the tailshaft housing.
I'll see if I can find a pic of mine. I used these parts when I machined my own SYE.

Edit: Pic added

[JohnBoulderCO]

That T-case info is good to know, thanks.

Keith,
Both modules are under the hood.

So, you could do a FSS (Front Sensor Splice) in front of the CAB (Controller Antilock Brakes) and the correct speed signal will be sent from the CAB to the PCM (Powertrain Control Module). Presto, the Speedo works! You still have front ABS. Later, if you want, you could figure out how to get the inputs from the rear shafts to get rear ABS back.

It should be easy to figure out which wires are coming from the front wheels and which from the rear.

John

[Mtn WJ]

Yep it seems we are getting somewhere. Thanks.

I cant wait to dig into the other axles a bit to decide on how to get rear ABS to work.

First things first GJH or Get Jeep Home.

[andyvillen]

Thanks for the info guys,

im going to be slinging a set of Mog's under a 99 grand cherokee limited, As soon as i figgure out why it wont start.

I think im going to machine the tone rings from the stock axles to fit on the hub of the mog axle. i think its my best bet.

Thanks,.

Andy

[FearTheDentist]

Thanks for the info guys,

im going to be slinging a set of Mog's under a 99 grand cherokee limited, As soon as i figgure out why it wont start.

I think im going to machine the tone rings from the stock axles to fit on the hub of the mog axle. i think its my best bet.

Thanks,.

Andy

That's what I did on my front 9" and have had no problems

[quadratokn]

I thought I could add some info here..

I found out that the speedo can work with only ONE speed sensor. Either front or rear, as long as one sensor works your speedo works. ABS is different story.

[iluvtruenos]

If it helps anyone, you can drop a 96+ T-Case from an XJ/ZJ into a 4.0 WJ.

It will bolt right up, and everything works. I've got a 242 from a 97 XJ in my 2000 WJ, and it looks factory. I see two advantages to this:

1. The u-joint yoke came installed from the factory, when I swapped on my u-joint yoke on a WJ 242, I always had 1/16" to 1/8" of in/out play even when properly torqued. This yoke doesn't have any.

2. It has the output speed sensor built into the t-case, which means that I can swap both axles and with a little rewiring of the ABS sensor can retain speedo.

[jclaudii]

Just a quick thing I found a user over on JeepFoum did, possibly even a member over here...he cut the d44a pumpkin out and replaced it with a standard iron d44. This way he has all the wj out and mounts, but the benefit of using a standard d44 for gear/locker selection. I mean you have to truss the hell out of it anyway, but they sell those as kits or you could fab up something. I hope to go this way when it's time to do a bit of upgrading instead of doing all kinds of axle swaps and hack jobs on my speedo...I'm just going to buy a used or broke d44a to use the shell/and axle shafts and then build on it until I break my d35 and swap

[ECGS]

Just a quick thing I found a user over on JeepFoum did, possibly even a member over here...he cut the d44a pumpkin out and replaced it with a standard iron d44. This way he has all the wj out and mounts, but the benefit of using a standard d44 for gear/locker selection. I mean you have to truss the hell out of it anyway, but they sell those as kits or you could fab up something. I hope to go this way when it's time to do a bit of upgrading instead of doing all kinds of axle swaps and hack jobs on my speedo...I'm just going to buy a used or broke d44a to use the shell/and axle shafts and then build on it until I break my d35 and swap

We built that axle and it is functional and verstile but in doing so we decided that the WJ's needed something better that was viable for production, so we went into R&D mode and out popped. The bolt in WJ Dana 60 -35 spline chromos- ABS compatible and accepts the factory brakes, all heavy duty brackets, uses spring isolaters and bump stops. check it out in the vendor section or build one online. http://eastcoastgearsupply.com/i-616...-assembly.html

[ArloGuthroJeep]

Doesn't hit the gas tank skid at all?

Now we need a bolt in front axle if we plan on keeping the same bolt pattern Otherwise running a 60 in the rear and a 30 in the front seems kind of pointless.

[AgitatedPancake]

Ryan it seems to use all WJ outers (brakes, etc), i'd bet those custom 35 spline shafts were made to the specs of the WJ including bolt pattern

[CrawlerReady]

I think he's saying because the D60 rear and D30 front don't go well together. So they should offer a front D60 with stock lug pattern