Diagnosing a Clutch Bearing or Bushing Noise
The Clutch Release Bearing
This applies force to the release levers or fingers. In doing so, the release bearing disengages the clutch. The release bearing is designed to operate with minimum friction between the rotating and stationary points of contact. If noise develops from the bell housing area, a few checks can be done.
Start with a road test of the vehicle. Listen for noise with the transmission in gear and the clutch pedal to the floor. Next release the clutch with the transmission in first gear. Noise under this condition indicates a worn release bearing or a worn pilot bearing.
To isolate the two, keep the clutch pedal on the floor and shift the transmission into neutral. If the noise persists, the release bearing is bad. If the noise is gone, the pilot bearing is bad.
A bearing noise that occurs when releasing the clutch pedal to engage the clutch while in neutral, but goes away when the pedal is depressed is caused by a bad transmission input shaft bearing.
Always make sure that all other components are in good condition. Check the clutch linkage for binding or mis-adjustments. Check clutch pedal free play and pedal reserve for proper setting. Check the clutch fork and input shafts for proper alignment.