Please Help! 2000 Chevy Tahoe, Differential, Spider Gears, Etc

[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?

[Draenor]

You would definitaly know of the spider gears are broken. Are you hearing a squeak from a dead stop to say 20mph? If so, check your rear u-joint on the differential.

[Matth3w]

No, it's like an "erp" noise...maybe akin to if you had the truck in neutral by accident, were on the gas a bit and then put it into drive when you realized it was in neutral.

 

It's a one time thing. I stop at the stoplight or stopsign, and sit there. Then when I release and hit the gas it goes "erp" and that's that. No more noise until I rinse and repeat.

 

He didn't say they were broken but that they could be going bad and if I let it go I could end up with a jacked up diff. I only have had sports cars before this truck, I bought it to be a second vehicle to my Corvette so I'm really not familiar with 4x4, trucks, etc.

[Draenor]

Still does not appear to be the spider gears. They would continue to make noise,especiall in the turns. There is no whining, that tends to tell me the gears are not out of spec. Do you have the G80 locker by any chance? It would be on your glove box, look for the RPO code G80. Thats the only thing I can think of withou being able to look. Yor going to have to get the cover pulled and the rear end inspected.

[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?

[DofD]

I don't think it's really the rear end making the noise. I've had my rear gears go out twice on me and both times they would whine constantly with the frequency depending on the speed.

 

In the Tahoe forum thread you mention that it sometimes does it going over bumps at slow speeds as well. Which doesn't really indicate a rear end issue.

 

If it were me I would be looking at the various bushings in the suspension.

 

Does the sound, sound metallic in nature?

[Draenor]

The spider gears would be grinding away, making all kinds of noise. That what I mean earlier "you be able to tell". It would be constant, not just from a stop or on bumps.

[L29er]

hey there i`ve replied to you in another forum...but check all cuspension components, bushings, spring hangars, u-bolts, and check engine and transmission mounts, if they`re bad they can rub on crossmembers and undesirable items... also check exhaust system, hangers insulators etc.