FOURTH regear ruined/distroyed!! diff problems...

Sooo... Let me start with, I have a 97' XJ, with 215,000 miles on it. I put a 4.5" lift on it and up sized to 33" tires. Also a new CV drive shaft, and degree shimmed the pumpkin for a shallower angle. Next logical step was a re-gear.
I have a manual 5 speed, so decided to gear to 4.10's. I took my jeep to Desert Rat, and they did the work. i had the jeep back about a week, and after following the proper break in procedures, I took it on the freeway (after the 100mile mark) and the rear end started to whine. Called and got my jeep back in. They said a bearing had gone out, and of course tore up the pinion and ring gear. They did it again, and this time I got my jeep back and the same whine came back before I had even gotten home. Called, took the jeep back. This time they re-geared with Yukon (not sure what they used the first time). Gears lasted less that 10 miles before same whine. The gears had been good for 215,000miles so obviously something changed/was ruined with the first re-gear. SO, desert rat replaced my rear axle (at no charge to me) and geared again. I had them put a locker in this time since they were in there. This time the gear break in was going great. Slow break in till 100 miles, then gradually more speed, faster takes offs, etc. Then today (after mile 220 or so) I was on the freeway today, about 75mph, for less that 10 mins and the whine started back up...
Does ANYONE have any clue what is going on or have any advice to offer??
I have an appt to take the jeep back again, but I don't want them to just keep throwing parts at it if there is something were all overlooking....

take it to a different shop that doesn't suck at gear setup?

what rear axle?

Chrysler 8.25. They've done tons of other's... Including a buddy with the chrysler.

lukemilt said:

Chrysler 8.25. They've done tons of other's... Including a buddy with the chrysler.

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But how many of those "tons" were different ones and not the same axle over and over and.....................................................

As stated, go to someone who knows what they are doing all the time, including Mondays and Fridays.

It sure sounds like you should choose another shop.

The 8.25 isn't even a challenging axle to set up. It has a crush sleeve for the pinion preload and one set of shims, the side bearings have adjusters. If it is consistently wasting the pinion bearings/losing preload I bet they are not properly torquing the pinion nut to get the crush sleeve to actually start crushing, but that is a gut feeling not really based on much.

Regardless of what is failing, you should take it somewhere else... and they should probably be covering parts costs for repair, four chances is ridiculous.

my first gut feeling is they are putting to much pinion pre load each time and killing pinion bearings. what about the front end- did you rehear that? bad U joints? other things causing this whine ? what about a wheel bearing?

I don't know how cordial the relationship is so far or what, but I'd be asking for money back to go elsewhere. If you press, politely, they should give it to you. At four times with no additional money, they may be glad to see you drive away knowing you won't be back. Everyone wants to make the customer happy but nobody likes working for free...

They're obviously doing something wrong whether they've done other gears or not. Time to get your money back and go elsewhere.

Some of the 8.25's don't have a crush sleeve on the pinion. Maybe they are just doing it the opposite way they should be. I'd say take it somewhere else.

Has to be bad setup. My guess is excessive pinion preload or failing to crush the crush sleeve. Is there any play in the pinion up and down or in and out? If there is then they did not crush the sleeve. As mentioned an 8.25 is not hard to set up.

dktool said:

But how many of those "tons" were different ones and not the same axle over and over and.....................................................

As stated, go to someone who knows what they are doing all the time, including Mondays and Fridays.

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HAHA!! Fair question!

yossarian19 said:

I don't know how cordial the relationship is so far or what, but I'd be asking for money back to go elsewhere. If you press, politely, they should give it to you. At four times with no additional money, they may be glad to see you drive away knowing you won't be back. Everyone wants to make the customer happy but nobody likes working for free...

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I agree. And before the 4th regear (where they also replaced the bell housing) he asked me if I'd lke a refund and ro try my luck somewhere else. Maybe I should go talk to them and give them the 'option' to get out before they do it again....

take it somewhere else and have him pay the bill........ a different shop will charge a different fee.
at this point i'd be looking to replace the axle housing too. 8.25s are cheap, something isnt right in there and it's best at this point to eliminate that as the possible problem.

(you already did that, i missed that part. )