Rhedalert

iTrader: (21)

Hi all,

Stock 2000 Camaro Z28, 2.73 rear end, 105k miles. Since I bought the car last month, I have heard a grinding noise coming from the rear. It is heard loudest while OFF the accelerator, going at least 30mph, and curving to the left. Heard a little bit while coasting straight or to the right. At first I would hear it while braking too, but after doing rear pads + rotors the brakes are quiet (rear rotors rotted and pitted). I can still hear the grind while braking too, but not as bad as before. Seems to be coming from the right rear but I am not 100% certain. Note that the sound is basically gone if I'm on the gas even a little.

The previous owner I thought had told me he replaced the left rear axle bearing, so I went ahead and changed the right rear bearing. Turns out either I misheard him or he was mistaken (or someone else did it), because the RR bearing was already replaced with one of those "saver" units. The axle is in poor shape where the old bearing rode, and it seems like the new saver bearing is very close if not touching part of this area. I'm thinking I should change the left rear, since it could be original still, and making this noise too. Any suggestions?


Thanks in advance!

Sean Collins

Could be either a bad axle bearing/hub assebmly on the right rear or right front or could also be a bad pinion bearing as its louder on decel. Get it to a shop that specilizes in driveline work and get it checked out.

Rhedalert

iTrader: (21)

well I'm thinking either the right rear axle is causing noise, again since it's pitted bad where the old bad bearing rode. And even though it has that "saver" bearing, it still sits very close to that groove.

Maybe the left rear could make the noise too, even though I "hear" it on the right side? The noise could be transferring and that's just where I hear it from the driver's position.

Rhedalert

iTrader: (21)

I'm going to change the left rear axle bearing tomorrow, if nothing else, to check condition of the axle too. I won't use that saver bearing unless I absolutely need it. It makes life very difficult when trying to reinstall the C-clip as there's less distance the axle will push inward.

That lock-bolt is a real pain in the *** too, that little 8mm thing. It strips if you even look at it funny!

Rhedalert

iTrader: (21)

Update/ Bump:

I changed the left rear bearing (original) looked alright, axle is in great shape. Noise still there, but the rear overall seems a little quieter. I used Royal Purple 75W90 gear oil this time around.

So I'm probably in the market for finding a good RR axle. I really can't think of what else would cause a grind noise such as that, and at those particular times too. My front hubs aren't the best either (like a whirring/ tire noise from the front at certain speeds and dependent on steering wheel position)

ddelallata

iTrader: (2)

My car did a noise similar to what you are describing, especially when turning to the left. It turns out that it was the Torsen carrier that was at fault. I replaced it with an Eaton Posi and the noise is now gone.

Rhedalert

iTrader: (21)

hmm... the more I think about it, the more I could see the carrier bearings causing the noise (particularly the right one) I'll look more into this!

turbotko

It's the torsen unit itself I bet. Mine makes exactly the same noise you are describing.......a dull grinding noise only on decel and mainly when cornering. If you even touch the throttle it completely goes away.

It made the noise when I bought the car. I've since completely rebuilt the rear with all bearings, 3.42 gears, and a used 3 series torsen diff. Noise is still there and appears to be getting louder. It sounds like helical gears rattling or grinding inside the torsen diff.

Dans2000SS

I had the same noise in my car. Found a pitted up axle same as you described, so I replaced both axles and bearings with Moser parts and noise was gone. I removed the ABS sensor's so I could push the axles in a little farther. That made it easy to reinstall the C clips.

Rhedalert

iTrader: (21)

I don't get any rattling. Just the mild grinding sound, and only on LEFT corners and off the throttle. I can sometimes hear it very slightly when coming to a stop, heading straight ahead. I wonder if thick gear oil would shut it up, if it were the problem?

I removed the sensors too, but installing the C-clip is still very tight. I noticed the C-clip WILL just fall out when I'm disassembling the axle. If I push in a couple times, I hear it drop. This happened both times so far. I have a good used axle coming in the mail for the right rear. It's best to replace it anyway. I'll see if this happens to be the noise I'm getting. I can safely pull off the right carrier bearing cap to inspect the bearing condition, without messing up the backlash, right?

Another thought: What if the noise is the inner end of the axle rubbing against the lock? Like if the surface is rough? I didn't look at it in detail, but can that be a source of the noise too? Considering on left turns, the right axle is being pushed "inwards". I also saw the inner end of the right axle looked like it had been overheated (bluing and discoloration)