A few months ago I noticed I was getting light oil leakage from a couple of seals on the front axle, tcase, and diff of my 02 denali, and since it had 120k I decided it was time to go ahead and replace them (and the fluids inside).

I replaced every oil seal in the drivetrain with a new GM OEM seal. All 3 on the front axle, both on the outside of the tcase, and the rear pinion/diff seal.

Since then, maybe 2 months, the pinion seal is seeping/leaking a slight amount. One of the output seals on the front axle is leaking a bit more, enough to wet the side of the diff.

We've had snow this week. Last couple of days I notice the snow under my truck is blue...dead giveaway that the tcase is leaking the autotrak fluid. I get under it and look, and the tcase rear seal where the driveshaft yoke goes in is really wet.

WTF? I didn't bend any of the seals on install, I used pipes, large sockets, chunks of wood, etc. to install them without bending or distorting them. The driveshaft front yoke is also brand new so it couldn't be responsible for damaging the rear tcase seal.

Is there some special procedure or magic trick for replacing these seals that I'm not aware of?

 

Did you install them dry?

 

The GM seals come with grease on the inner lip already, and I used vaseline on the outside edge and the metal bore they were going into.