Hey, All. I have a 99 Jimmy that I've recently got after I got rid of my tahoe. I have done some work, redid most of the front end but neglected to notice the leaking front diff from both axles, and have had a squeaking that use to only happen over bumps (assumed it was suspension related) but now I am starting to think it must be driveline because the squeal happens at full stops and I can make it stop by grabbing the front drive shaft and pushing and pulling it. I know where to start, leaks obviously but I cant seem to find ANY info on this all.
the sound seems to be coming from diff or transfer case mounts maybe. Just not sure where this squeaking could come from
the sound is intermittent and cant really reproduce it, but seems to happen more after driving for 15 20 minutes

 

I know my leaf springs squeak because I havent changed those little round "bushings"? Between each leaf at the end... that and some other old crappy sway bushings...

I dont think I ever had squeaking from the diff tho, and mines had a slow leak for a good while...

I'll be doing a rebuild on the new zr2 diff I got going in, so that'll stop the leak.

edit: I wonder if the bushings in the diff are causing the squeak?

 

I dont know if it is the diff forsure but I do know that grabbing the front drive shaft and manipulating it makes it stop when it does happen so it must be somewhere between; either diff or transfer case or maybe just mounts.

It's very odd and havent ran into the issue before with any car, I havent used 4x4 much since I got it but never had any issues with engaging or any sound from it when I did do some crawling, I swore it was suspension till it started happening at full stops

 

How old are the front ujoints on that little shaft? Ever been greased?

 

Not to sure, exterior wise looked good after a brief look but I do think they are original still because I didnt see any zerk fitting on them

 

So went for a drive and 100% coming from or near the TCase, not the diff. but what would it be, an issue internally or possibly contaminated fluid. I think it must be a mount based on the type of noise. but I am not sure what worn t case symptoms are