billy mild

I have noticed when my car is being driven for the few blocks that when making a left hand turn I hear a popping/clicking noise from the rear of the car. It sounds similar to when I am letting the clutch out, but happens through out the turn usually when under a little throttle. Right turns there is no noise at all. I may setup my go-pro and try to get some recordings of it.

Arctic91

When was the last time the diff lube was changed? I had a popping noise from the rear that I thought was bearings or maybe U joints, mostly on acceleration or when turning. After new Mobile 1 diff lube and GM limited slip additive, the noise was gone. If the fluid is old, that might be a good place to start.

Scott

billy mild

I changed the engine oil, transmission, and rear diff fluid not even a year ago. I used Mobil 1 75w-90 in the rear diff.

I did not add any LSD additive. I was under the impression its not needed with Mobil 1.

Arctic91

I also thought that Mobil 1 had the limited slip conditioner, but I was told that I still needed to use the GM additive. It definitely solved my problem within about 10 miles after the change. If the fluid is good (and you don't need the additive), then you may be experiencing a different problem than I had.

Scott

oldpro

still a good ide to add the gm additive but I would take a look at your rear wheel bearings and see if you have any play there

billy mild

So you had just Mobil 1 in the rear diff and it made a popping noise. After you added the GM additive it stopped? I wouldn't think that the LSD additive would be needed. Also why does it only make it on certain turns?

I originally thought maybe U joints for the driveshafts. Wheel bearings when they go bad usually make a whirring noise. I'll see if I can get a video of it.

Arctic91

No, my fluid was just old. I'm not sure what the previous owner had in there, or just how old it was, but I replaced it with new Mobil 1 and GM additive and the noise went away.

Scott

Paul Workman

Add the GM friction modifier to the diff. if you want to (should do, methinks). But, my money is on the hub or half-shaft U-joint needing to be replaced, based on your description.

Coupe89

When mine did that. My half shaft U-joints were shot.
After I replaced them the sound when a way.

billy mild

It sounds like it could be the bearing or the u joints. I just bought all new bearings. I know the passenger side bearings had some play, I don't know about the driver. Some people have said it is okay to have some play. My understanding is that there should be no play in wheel bearings.

Here is a video of the noise.


It is around the 2 second mark. Almost sounds like a slight rubbing noise.

Is there anyway to confirm that my U joints are bad?

ken4

I would try the additive first. You would not believe the noise I have seen different cars make with out it. Especially since you did not put it in after the fluid was changed. Cheap and easy. It will take a little bit to work its way in.

billy mild

My thinking on the LSD additive is that why didn't this noise surface last year. I have put a couple thousand miles on my car and just now it is needing that additive. I'm sure its cheap, but I know putting too much of that stuff can/will affect how well the LSD locks up.

Is there a sure way to test or evaluate the U joints before trying to remove the halfshafts. Is it true that the camber bolt needs to be removed in order to get the halfshaft out?


Found this youtube video. Looks like I can apply this to the vette.

billy mild

I replaced both of my rear wheel bearings, that did not fix the issue. I still have a squeaking/chirping noise when going straight under acceleration. Sometimes on deceleration there is a noise as well, but much less noticeable.

This must be the U Joints. When I had the car jacked up I didn't notice really any plan in the u joints, but then again it wasn't on the ground.