I posted his same problem in the Newbie section a few days ago but I haven't gotten any response there, so I decided that I would try here to see what I could get. My buddy has a 95 tahoe 4x4 with an auto tranny. Just the other day it started to develope this weird clank/ping noise coming from the rear end somewhere, I can't exactly tell where on the rear end it is coming from, almost sounds like it is coming from the axle or the drive shaft. I don't think that he could have broken the axle because he really doesn't do a lot of extreme stuff with it to where he could break one. What I'm thinking the problem is, is that there is too much lash in a gear somewhere causing the noise. Because you hear it once when shifting from like park to drive. Then once you get it up to about 1500 RPM it starts pretty bad and it doesn't go away until you push on the breaks and get the RPMs down below 1000. Also I don't know if this could be a problem but could a wheel bearing be going out on it, and it is just starting to go out and as a result it only starts to make noise at a certain point :confused: , Just some of the ideas that I have about the noise, any help would be great.

Sounds like a u joint. They will usually Ping when they are starting to get alittle sloppy. Just my .02

Thanks man, I might have to have him check that when I see him next.

Probably a good idea to drop the rear diff cover and check for chunks. 10 bolts of that era are not known for their longevity even in street vehicles.

But if it is something in the diff wouldn't it make that noise all the time no matter what gear you were in and no matter how fast you are going

Depends on what is going out.

Well in this case is there anything in particular that could be going out based on what we know so far.

I had a 2001 Chevy truck and it did what you are descibing. it was the cross pin coming loose. The bolt that holds it in sheared and the cross pin was working its way out.

could possibly also be a broken snap ring on the transfer case output shaft; fairly common problem. :)

Do post what you find out. Dont leave us hanging

Yeah I will let you guys know when my buddy gets it fixed if he ever does, but it has kinda seemed to have gone away for the time being, we were out at folsom lake today, and he drove right by me twice in one of the parking lots, and I didn't hear a thing, unlike when we first started to hear it you could hear it from pretty far away.

Yeah my truck took spells where it made no noise at all. But when i finally pulled the dif cover and found that cross pin just held in by it self. Also destroyed the carrier to. It was cracked at the bolt hole that held it in. Now imagine that cross pin coming out at 70mph, it would lock up both rear wheels for about 1 second. Then it would start breaking every thing. I have also broke the spder gears on a separate time. I keep hearing a pop but then it would be ok, one day a piece of the gear came out the cover and knocked a hole about the size of half dollar. The only way i found out the hole was there was due to me living on dirt road and all that gear oil collected dust on the tail gate and the funny smell.

Its probably the lash, my 03 pops sometimes when is shifts and Im cornering, It has done it since it was brand new, and I have asked everyone that i know that has one of these and they say the same. a bad u-joint would amplifie that during variation of torque, but if it does it continuously at time, I would pull the cover like others have stated, if a cross pin comes out it will take out your housing, and everything inside it, plus it could cause an accident, its only 10 bolts and a quart and a half of gear lube to be sure..