Spider gears, differential? HELP! 2000 Chevy Tahoe

[Matth3w]

See:

http://www.tahoeforum.com/showthread.php?t=11641

I took it to a shop, had the rear brakes replaced, which I was told would probably stop the sound. While the brakes were indeed TERRIBLE (shoes in the rear were worn to the rivets) the sound did not stop. Talked to the owner of the shop that replaced my shoes, drums, and fixed the front diff leak and he said he had a 99 Tahoe that made the same sound (only less pronounced).

He said barring a complete clean external inspection (bearings, rods, bushings, etc) he could almost guarantee 99% that it was something to do with the spider gears in the differential, and if left to its devices for too long, could result in a bad differential.

What are your thoughts on this?

 

[Matth3w]

The sound is basically like if you had an automatic car in neutral and gave it gas without realizing and then put it into drive how it gives that little squeal. I really don't know how to describe it.

I noticed just now on my way back from the gym that it sometimes does it when stopping as well, with no accelerator depression. Like if I'm coasting and then kinda jab the brakes you can hear it squeal. Also, sometimes it does it if I go over bumps at slow speeds.

Would the spiders/diff make a noise going over a bump if it was bad?

 

[Sepiroth]

Generally the purpose of spider gears are to keep everything in sync as you are making a turn. When you turn, one wheel is going at a faster speed than the other.

IF there is an audible humming at a constant speed or accelerating from a cruising speed, i would say that you may have an issue with the pinion. If the sound is humming while coasting, i woulod say then that you have an issue with the ringn gear. Now it could be as simple as bearing replacements or at the very most a rear end rebuild.

I would also suspect the drive shaft u-joints too.

Its hard to diagnose sounds over the net, much less through a forum. Your best bet is to find a place where people know their stuff. I would recommend a drive line shop.

 

[u2nv]

+1 hard to diag over net but im guessing suspension noise or u joint take it to a good shop if you have one??