O2Form

Just had the pinion seal replaced and we found the old seal was OFF CENTER in housing<NOT TRUE, I FOUND THE YOKE IS RUNNING OFF CENTER. The yoke was only contacting 80% or so of the seal. If the new GM seal doesn't solve the trouble then something else is off center. The yoke looks perfectly round and there are no vibrations but it does explain why this pinion seal is always leaking.

When we replaced it one year ago I can't remember what the pattern on the yoke looked like but i'm sure it was completely around. I figured it was leaking because it was at 60k miles.

Setting the pinion preload is a real touchy thing on these 10 bolts if you ever do one. The final adustment tighting the nut is EXTREMELY touchy. Best to cloesly pay attention to the preload and feel BEFORE you remove the nut and mark it carefully. IT MUST go back very very close to where it was. Even a little more or less makes a huge differeance in preload.

01ssreda4

iTrader: (96)

Coulda been a faulty made seal. Who replaced it? It should have been easy to tell what was not centered with an experienced eye.

O2Form

It was a NAPA seal but the more I think about it I'm sure its not a seal problem. You can clearly see the wear marks on the yoke and they do not go all the way around the yoke. This means the yoke or pinion are not centered for some reason. Damit I guess another seal change is in my future......****!

If the seal was off center the wear marks on the yoke woooood still be all the way around. The wear marks on the yoke show the seal is contacting it about 80%, i'm guess the yoke turning about 30 thous off center. There is not enough room to get a dial indicator on the seal surface with the yoke installed because its the second design.

I hope the factory seal we installed has a little more coverage but I don't think it will cover 30 thous or so run out. plus all that run out is constantly flexing the seal so its going to wear much quicker than normal. If it leaks again i'm going to pull the sleeve off the yoke and check the runout then install the 1st design seal<what I should have done.

01ssreda4

iTrader: (96)

Nope, a seal just can't work against something so out of round. I'm wondering how this happened....remember the pinion bearings and gear are what needs to run true. The yoke simply rides on the spinning pinion..though I suppose the yoke could have gotten bent. Hard to say without an in-person inspection.

O2Form

Wish I could get a indicator on it. It runs nice and smooth even at high speed. No vibration etc. The drive shaft seems to turn true but i didn't try measuring it. At least I know why the seal is leaking. I can't imagine the sleeve could be off that much.

O2Form

I just remembered something.......this car was in a bad accident before we bought it. It was hit in the rear drivers side hard. how much you wanna bet the pinion has a slight bend in it?

Time for some Lucas oil thickener!

SS SLP2

iTrader: (8)

hard to beleave the pinion or the yoke would be bent from a accident I think the housing would go before eather would bend,I would guess eather were bent they would wipe out the pinion bearings out very quickly
Johnny

O2Form

I agree but the rear is quiet and runs smooth, I noticed some very odd marks around the seal area with the seal removed. Looks like someone drilled and tapped a hole in the face of the housing but it went sideways off the face. Also some rasied marks we removed with a file. Strange stuff.

If it leaks again it will be getting Lucas.