It sounds like either the pilot or input shaft bearing and or the throw out bearing is bad. The reason the noise might not be there when you put it up on jacks is because there is no load on the power train. This can make a difference as parts don't push against each other in the same manner as they do when in an under load condition. So, I would guess, especially with the mileage, that it is about time to change the clutch and the pilot and throw out bearings. Of course it is hopefully not an input shaft bearing which would require the gearbox to be rebuilt. If the engine mounts are letting the engine move at all, check this by putting on the parking brake with the hood open and give it a little gas in first gear and see if the engine hops up or moves abruptly. It should not move much at all.
Most kits for a clutch replacement come with pilot and throw out bearings so you should be okay by just replacing the clutch as long as the input shaft bearing is okay.
SPONSORED LINKS
Tuesday, July 7th, 2015 AT 5:24 PM