Ok...so my car developed this weird whining noise the other day. I thought the diff lube was low(the pinion seal has a slight leak), so I added lube and posi additive. That didn't help at all. I just installed a new SPEC cluch and slave cylinder about 3 months ago. It makes the noise when I am decelerating with the transmission in gear (downshifting) or when I am driving and I let off the gas while it is still in gear. If I accelerate, no noise. It also whines when it is out of gear while I am slowing down. I dont know if the transmission is going bad (ie the main bearings inside) or if there is a problem with the rearend. The tranny is the original with 133,000 miles so if it is going bad, I wouldnt be surprised. Thanks for the help guys.

Kiel