Anyone experienced this issue? I'm confident enough to do it myself but concerned about the bearing preload. Some say it's sufficient to mark the pinion bolt and just make them line up when retightenening the yoke, others say you risk crushing the crush sleeve.

 

not me, i chickened out and had a shop do mine.

 

Yeah thats probably the safest option, the proper method says to replace the crush sleave and re-torque properly, which requires complete disassembly of the diff. Seems a shame to go through all that hassle over a small leak, but hey, such is life.

I'm thinking i might risk it as there are countless videos on youtube of people doing it simply by re-torquing the yoke nut back to the same position it was in before removing it. (ie count the number of rotations of the nut when removing it, and using a painted line to get the position correct)

If I have a catastrophic diff failure, i'll be sure to revive this thread!

 

I have replaced several pinion seals and not had a problem.
Yes remove the nut - use dial or scale torque wrench to get loosening torque, remove yoke, replace the seal. and emery paper the seal riding surface on the yoke.
Lube lip of seal with gear lube, install yoke, and tighten nut to crush sleeve using torque value when loosening.


Crush sleeve will tell you when you're there, can't really overdo it.
Never had a problem later,

 

Awesome thanks heaps!! I have got the seal out, now i just have to wait for shipping to New Zealand.

Out of curiosity, the pinion bearing has TIMKEN labled on it. Did GM use timken bearings in a stock 10 bolt posi on 4th gens?

 

I would say GM used the cheapest supplier as GM/EATON, would have bought a LARGE qty of bearings, just like companies bidding on jobs, the cheapest is accepted.

 

I thought TIMKEN were a premium brand though

 

Yes, they are.

 

GM has all the major brands quote every bearing. To meet the standards they set to be allowed to quote is the tuff part. Once they pick a vendor for a design they are all but locked in. It takes several QA or delivery issues to loose the OEM on a part. New designs is when manufactures change the most.

Companies live off being the OEM. They make crap profit selling to GM but they make their money in replacement parts. GM is hard core about what it cost to make a car, but with non-warranty parts you can charge almost what you want and GM will X3 it and let you have it