There is a speed dependent rotating sound that sounds like it coming from behind the stereo. The sound starts from anywere between 10-20mph and quickens the faster you go. I believe it was changed when the previous owner did a full rebuilt about 6000-7000 miles ago. Is it possible that it went out or is something else? When I had the transmission out a few days ago to do the clutch i felt the pilot bearing and it felt smooth to me. Anyone got an idea?