91 firebird with 4th gen Torsen. Used old seal and leaked (I think I messed the old one up while prying the yoke off.) replaced it withmaster pro pt8610 I tried my old yoke and the one that came with the diff and both leak. Put sealant on the yoke spines. I didn't put any sealant on the seal itself or lube the rubber seal. I tried to move the yoke with the nut on and all it does is turn slightly. Should the yoke slide all the way in to where you can't see the shiny part??
Any clues to give me would be appreciated!

More info: I used the old nut but it seems tight enough. Also used the crush sleeve that came with the differential. Used the same shims theat were in my old diff.
​​​​​​​. I'm stumped here I'm going to buy another seal and try lubing and sealing it tomorrow..
​​​​​​​Thanks

 

When you replace it, be sure to put a thin bead of RTV or similar sealant around the outer portion of the seal where it seats in the diff. Everybody has their preference, but I bought my pinion seal from the dealership. Also, I wouldn't recommend reusing the pinion nut. Some may disagree, but the GM manual says to replace it. They are cheap, even from the dealership. Unless you enjoy correcting pinion leaks.

 

Thanks for the info! Now is there anyway to know if pinion preload is off? When we installed it I forgot to set it (I know I know I just ran it down with a 1/2" impact, it's a used setup btw. ) It doesn't make any noise however and I'm trying to justify not tearing it all apart again.. Don't want it going bad in a couple thousand miles either..

 

You don't set preload unless using a new crush sleeve. If you are just doing the seal torque it to 150 Ft/lbs. This is enough to insure is doesn't come loose but not further crush the sleeve.

GD

 

That is a huge relief!! I was really worring about that! Phew! I'll report bak after installing another seal.

 

Turns out the seal I bought was defective. Bought a new higher quality on and no leak yet after a few hours! Thanks everyone I think the problem is solved