[steelshot]

my brother in law asked me whats involved in replacing the oil seal at rear yoke 2003 tj stock is it just take off nut and slide out then reverse to re install?is there a crush collar?thanks this is for the rear diff,

[rallynut78]

here is a write up i found on how to do the job maybe this will answer your question

http://www.madxj.com/MADXJ/technical/technicalfiles/SRpinionSeals/PinionSeals.htm

actually I think it does. "Note that the Dana 35 axle uses a "crush sleeve" on the pinion bearing."

[Nonya]

Do a search,plenty of info about it.My educated opinion is if you have to ask about it you shouldn't touch it,changing a pinion seal is a highly skilled job.Anyone can pull it apart and put a seal back in and tighten the yoke.Only someone with training can do it properly.I've seen so many different ways of doing this posted and honestly there is only one proper way.Tread lightly,Pinion bearing failure can cause alot of damage.<the usual result of improper pinion bearing preload setting after changing the seal.

Another thing to ponder is if your local repair trained to properly change the seal?You would be suprised that very few know how to do PROPER repairs on differentials.

DO NOT follow the info at the above link....its useless IMO,it has just enough info to get you into lots of trouble quick.Before the seal is changed a few simple tests must be done to KNOW why the seal failed.Without this knowledge you best not touch it.

[rallynut78]

Originally Posted by Nonya

Do a search,plenty of info about it.My educated opinion is if you have to ask about it you shouldn't touch it,changing a pinion seal is a highly skilled job.Anyone can pull it apart and put a seal back in and tighten the yoke.Only someone with training can do it properly.I've seen so many different ways of doing this posted and honestly there is only one proper way.Tread lightly,Pinion bearing failure can cause alot of damage.<the usual result of improper pinion bearing preload setting after changing the seal.

Another thing to ponder is if your local repair trained to properly change the seal?You would be suprised that very few know how to do PROPER repairs on differentials.

DO NOT follow the info at the above link....its useless IMO

I used it to do mine and it was pretty straight froward. (IMHO)

[Nonya]

Originally Posted by rallynut78

I used it to do mine and it was pretty straight froward. (IMHO)

no offence but if you followed that info and your rear doesn't fail you are dam lucky.I've repaired 100s of rears,trust me on this.

[Rollin]

Originally Posted by Nonya

Another thing to ponder is if your local repair trained to properly change the seal?You would be suprised that very few know how to do PROPER repairs on differentials.

DO NOT follow the info at the above link....its useless IMO,it has just enough info to get you into lots of trouble quick.Before the seal is changed a few simple tests must be done to KNOW why the seal failed.Without this knowledge you best not touch it.

What is so hard about changing the seal? You say its easy to eff it up, but to replace the seal, you dont have to replace the bearing so there is nothing screw up except the seal.

Did you ever think that seals just wear out after a while? If I replaced the seal 10k miles ago then I would go rooting into the cause, but after 120k miles like my Jeep has on it, things are going to start wearing out. I am doing the seal tomorrow, and I am certainly not going to look for the cause of its failure.

[rallynut78]

Originally Posted by Rollin

What is so hard about changing the seal? You say its easy to eff it up, but to replace the seal, you dont have to replace the bearing so there is nothing screw up except the seal.

Did you ever think that seals just wear out after a while? If I replaced the seal 10k miles ago then I would go rooting into the cause, but after 120k miles like my Jeep has on it, things are going to start wearing out. I am doing the seal tomorrow, and I am certainly not going to look for the cause of its failure.

amen!

way to think outside the box!

firts try to fix it yo self for $20 then if it starts leaking give someone else $200 to fix it!

[dragginwagon406]

Definitely seem to be some details missing from the madxj write up. When I had mine apart, I tried to get away with resuing the old crush sleeve and when trying to set the preload on the bearings I ran the original pinion nut up with the impact wrench and I went too tight - very hard to turn the pinion. There was no going back, the crush sleeve ended up loose on the pinion. Ended up replacing the crush sleeve and pinion nut.

I'm not saying you can't get away with reusing the original crush sleeve or pinion nut. Just if you want to reuse them, turn your pinion back and forth to get an idea of pinion bearing preload and mark the position of the nut relative to the pinion before disassembling. When reassembling, keep an eye on the pinion bearing preload as you tighten the nut by hand. For reference, you should likely end up close to your mark when the bearing preload comes back near where it started(actually, it should have a little more resistance due to the new pinion seal).

If for some reason your preload gets out of whack, at least you know and can address the problem before you drive it.

I'm all for the $20 fix. Pinion seals can wear out due to age but also, bearings can fail and cause the pinion to walk in the housing. Do yourself a favor and before you take it apart, check for any abnormal play in the bearings indicating the preload is gone.

[Kiwi Jeeper]

Originally Posted by Nonya

no offence but if you followed that info and your rear doesn't fail you are dam lucky.I've repaired 100s of rears,trust me on this.

I am not doubting your knowledge, but whenever someone has said "trust me on this" I have gone the opposite way and never regretted it.

[AROSETO]

I've done my own and others pinion seals previously and have never had a problem. I've seen friends take their jeeps to an experienced repair shop to have pinion seals replaced and a week later they begin leaking once again. Of course there are the exceptions. I trust myself before I trust someone else with my jeep. And if I f' it up then its my fault and I have to pay but I'd prefer to blame myself then someone else because that could turn into a huge hassle.

[dragginwagon406]

Blindly retightening the original pinion nut with an impact will likely lead to long term problems.

[Kiwi Jeeper]

Originally Posted by dragginwagon406

I'm all for the $20 fix. Pinion seals can wear out due to age but also, bearings can fail and cause the pinion to walk in the housing. Do yourself a favor and before you take it apart, check for any abnormal play in the bearings indicating the preload is gone.

I agree, you need to investigate and make sure that the seal has worn simply because of old age. If there are any reasons, they need to be addressed at the same time. I just checked the FSM and there is a definite difference between procedures for a D35 and D44, OP needs to check which one he/friend has.

[Nonya]

Originally Posted by dragginwagon406

Blindly retightening the original pinion nut with an impact will likely lead to long term problems.

The write up on that page should also lead to brain surgery,that's what you will wish you tried instead of overtightening the pinion preload.

It is IMPOSSIBLE to reuse the old crush collar and tighten the nut with a impact wrench!If you try it you will be visiting your favorite shop in about 100-500 miles for lots of expensive work.

Like i said you must do a few simple tests before digging into it AND must know the rules.You wouldn't try replacing the windshield in your jeep and i'll bet its alot easier to get right than blindly changing the pinion seal.

Originally Posted by Kiwi Jeeper

I am not doubting your knowledge, but whenever someone has said "trust me on this" I have gone the opposite way and never regretted it.

Even a blind squirrel finds a nut once in a while

[subaruboy]

Anyone here who has had the job done in a shop... how much did it cost? I'm not sure I'm comfortable enough/have the means of doing this myself... but if it's going to be a couple grand, i might as well just keep dumping oil into the pumpkin until I can just throw that couple grand towards a new axle (i have the d35).

just looking through the FSM and reading the procedure that's in there, it seemed like it would be expensive

[Nonya]

75-100 dollars at the most unless there are other problems causing the leak.Be sure to take it to a quality shop.