About 2 weeks ago started noticing something like a whirring noise. Noticed it only seems to occur noticably when I am accellerating in gear, sound does not happen when revving in nuetral. Did notice today I can slightly hear it by having the car in gear and barely letting up on the clutch while driving. I took it to 2 shops who seemed to have a hard time understand what I was hearing. Sound like a familiar problem? I did some googling and best I could come up with fluid or pinion gear. Fluid is full and according to the tranny shop pinion gear noise should happen when you're moving and not in gear as well. Just a background, about 2 months ago noticed a distinct grind from 4 to 5. Went ahead and changed the fluid out (Redline MT-90) and noticed no change. Seems like the grind from 4 to 5 isn't as bad now a few months later. Any chance there's some debris floating around in there?