I’ve had a ticking/clicking noise coming from the rear of the car while driving at posted speeds. I also have a scraping/grinding noise while driving at parking lot speeds. It doesn’t whine any more than other GM’s that I’ve owned. It is actually quieter. It seems to get worse as it warms up. I’ve taken it to a local tire shop to see if they had any ideas. They checked the brakes and they were OK. They said it might be in the rear end. Of course they don’t do that kind of work. I talked with a friend of mine who is into GTO’s. He said to try changing the rear end lube and adding the GM oil additive. I did that the other day. I actually put two bottles of the additive in. I’ve only driven it about 50 miles and the noise seems to have let up a bit but it is still there. Any other ideas? Gears, bearings, clutches? It is a G92 rear end with 3.42’s and disc brakes.

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91 Z-28 1LE
305,5spd
White
Flowmaster
K&N filters
JET Airfoil
<http://www.picturecd.com/system/login.cgi?username=cyetter&album=91+Z28+1LE>

98 Chev Silverado Ext Cab 4x4
Green
Dual Flowmasters
K&N air filter
B&M Shift Plus

 

Rear end gears tend to whine if they are not lined up perfectly. If yours are stock, and you havn't added a LSD it's unlikely that that is your problem. However, there could still be something going on back there.
When did you last change the diff fluid? (see owners manual for suggested intervals)

I hope it's not the gears, replacing them is a time(or money)-consuming task.


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James D Montigny
1992 Pontiac Firebird 5.0
Bone Stock Officer, I Swear !

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