McGinnis

I had a new ring and pinion and carrier unit put in about 6 months ago, with 3,000 miles on the car since. I recently replaced some older tires that were very noisy, and since have noticed a pronounced whine from the rear end of my car, the old tires drowned the noise a lot. It is quiet from 0-40mph, and starting around 45mph and being the worst around 60mph it has a high pitch whine when I let off the throttle or accelerate with only light throttle. It is silent when I accelerate normally from a stop, and when fully letting off of the throttle. Would loose pinion preload do this, or do you think it's just "gear" noise from not being OEM gears? The parts used were U.S. Standard gear 3.23 gears and an Eaton posi, unit which is dead quiet around corners and works great. The shop I brought it to replaced all bearings at the time, and the car is a 1999 firebird formula with 48,000 miles. I pulled the gear cover off after the first 1,000 miles and the gears looked ok with a decent amount of shavings, which I figured was just part of normal break in.

01ssreda4

iTrader: (96)

I can't say I agree with the shavings part. New gears and bearings shouldn't give off much....though those could be from the posi unit. I would monitor the noise, unfortunately once changed from stock it can be difficult to get a dead silent rear end, even when you know what your doing. The truth is tolerances can be set right and if the teeth mesh just a little off you get noise. Doesn't mean the rear will fail, its more of a minor annoyance. In conclusion, if the noise gets worse, then worry.