Ever sense ive owned the car it has always made a whining noise from the rear end. I poped the diff cover and had one my dads friends that is a machinic look at the ring n pinion. It has a 9 bolt 3:27 posi and appears that all is ok in the diff, all the bearings seem tight theres no abnormal wear on the gears, replaced the u-joints theres no slop in the driveshaft but yet it still whines under acceleration and is louder on the de-accel (as soon as i let my foot off the gas) Any suggestions? Is this normal for a car with posi?