96 Grand Dana 44 Aluminum Rebuild pinion setup questions: Shop Teacher needs teaching - JeepForum.com
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Unread 03-25-2009, 09:42 PM   #1
twisted_ed
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Join Date: Jul 2004
Location: Courtenay, British Columbia, Canada
Posts: 1,350
96 Grand Dana 44 Aluminum Rebuild pinion setup questions: Shop Teacher needs teaching

Hey there, it has been some time since I was last on this site, probably 4-5 years when I was in college building my Cherokee while getting my teachers degree.

Well now I am a shop teacher and teach automotive and I am in need of help.

I have a student with a 96 jeep grand with the infamous Dana 44a axle. Well the kid bought the jeep with a tweaked axle and bought a junkyard housing to replace. Had he known anything about his jeep when I asked him questions prior to him bringing it in I would have advised him to swap in a 8.8 since he's running 33s on the vehicle but long before I saw it he called it a Cherokee (my jeep of choice), and assured me it was an iron axle, well that went out the tube when I showed him the magnetic base would not stick to the housing but by then it was tool late, anyways before he brought it in I assumed dana 44 was swapped in by previous owner, an iron one a good one so I didn't recommend the swap, even thou I chose the 8.8 for my swap years ago.

So now we are at the point of reassembly but in my underfunded shop with no specialty tools I do not have a pinion depth tool so I need to know a couple of things if someone can help:

This 44a uses a crush sleeve, for shim settings can I simply place the new pinion races in the housing assemble the pinion with the old crush sleeve, put on the yoke, and tighten the pinion nut (old one at this point) to the correct torques and preload settings throughout out trial and error mesh pattern and backlash settings then when found the correct, remove the setup bearing on the pinion, press on the new bearing with shims and then assemble with the new sleeve and pinion nut? or do I need to use a new sleeve every time (expensive). I would assume that as long as I set the pinion preload correctly with the old sleeve I should be okay, it works in my mind though I could be missing something, I am not the greatest axle guy.

This is how I did my personal 8.8 and the jeep still runs perfect 6 years later so I know I did it right before but I believe the manual told me to do this, my AllData program says to use the pinion height tool. We can't afford this and I know that trial and error using the old shims works. Any suggestions to making this setup quick and painless.

__________________
1990 Jeep Cherokee Laredo
4.0L
Automatic Tranny
NP242 Transfer case
Dana 30 front, 35 custom rear differentials

Mods:

RE 4.5" Lift
32x11.50 BFGoodRich M/T KM's
American Eagle 058 Polished Aluminum Wheels, 3.63" BS.
Grand Cherokee Rear Disc Brake setup
Custom Downpipe W/ Cat Removed.
Dynomax Super Turbo Muffler.
Surco Roof Rack

My Jeep
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Unread 03-25-2009, 10:07 PM   #2
baxy
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I wouldn't be too worried about pinion preload on your testing setup, a hair past zero would be fine.
Now most likely you do not have the revised procedure and specs for aluminum diff set up. this doesnt matter anyways because special dummy bearings are required.
So what I would do is start with the old pinion shim which most likely will be right on.
Then when doing the back lash and bearing preload for the sides start with the origional shim on the ring gear side and for the other side subtract .005" from the origional shim and start there.

The reason these axles EAT side bearings is because DANA assembled them in the factory using the cast 44 procedure which was to shim the backlash to zero and force the backlash and preload using the other shim... since cast doesnt swell as much as aluminum this works perfect, for cast but not so good for aluminum

ok back to the set up
after you have a good patern and good backlash
set your pinion turning torque and write it down
install your carrier torque bolts down and confirm your back lash
now retest your turning torque (pinion plus carrier)
should go up by about 6 to 7 inch pounds
multiply the difference by your gear ratio to get the true turning torque
7 x 3.73 = 26.01 which is a good number for new bearings
if your total turning torque is too high remove a little more shim from the side opposite to the ring if it is too loose add a bit , no telling if this procedure has been done to this diff already or not

in the beginning when these jeeps were under warranty and before side bearing failure became an epidemic we just zipped them apart slammed in new bearings and kicked them out .... well 20k miles later they would be back with ruined bearings again

important to use a torque wrench on the ring gear bolts if you have the ring off the carrier flange is very flimsy and if you use an impact you are running the risk of creating run out in the ring as wellas snapping one of the NEW bolts your going to get
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