Have 200miles on a new set of Precision gear 3.73 with a rebuild kit..I noticed today that I have some constant buz coming from the rear end it is not loud and can be hear from 30mph above. The sound doesn't seem to get louder on or off the gas and doesn't seem to get louder at highway speeds. I don't call it a whine cause my T-5 whines and I know the difference..it's more of a quiet hum or buz, is this normal cause I know at 30mph would be the same as 60mph with the old gears in terms of driveshaft turning so I wounder if it was always there and I never noticed before...also...yes I need and have coming an aluminum driveshaft cause there is some vibes going on.