BrianB

This is going to be hard to put into words but here is what I am dealing with. First off it only makes this sound when the throttle is applied and takes a few minutes of driving before it will start. The noise is similar as to someone making a SHHHHHHHHH noise implying for someone to be quiet. When you let off the gas it goes away and with any type of blip of the throttle you can hear it. Also while driving I can put the car into neutral (automatic) and the noise disappears completely, even when revving up the engine. As soon as the tranny is engaged back into drive and throttle applied the noise will come back.

Now this is a fairly new rebuilt rear end with appx. 7k-10k miles on it 3.73 motive gears, new posi, bearings, t/a alum. cover. I took a peek under the car and noticed that the differential cover is leaking a bit. I don't know for how long but I assume it was since my last differential oil change about 6 months ago. My best guess would be that I am low on fluid and that this is causing the noise. However, before I change the gear oil and seal up the cover better. Could this be something (low fluid level) that could cause this noise? Thanks in advance for your help!

8a8mfh

iTrader: (3)

I have the same noise that started after motive 3.73's and an AAM cover. Except my car does it while coasting. No idea what it is.

TX99LS1

Pinion bearing maybe??

8a8mfh

iTrader: (3)

Not here, I took mine back apart, nothing unusual.

BrianB

Well the whole low gear oil theory is out the window. The cover was leaking so hopefully I solved that problem, but the noise is still there. It is hard to explain. Maybe it is just normal for theses gears once they get worn in?