Schaeffler 99905221001 Clutch Pilot Bearing – Porsche | 99905221000

A pilot bearing is a grease packed and sealed roller ball or needle bearing that supports the input shaft of a manual transmission in the rear end of the crankshaft or flywheel. Pilot bearings allow for speed differences between the crankshaft and transmission input shaft when the clutch is engaged to shift gears. Some vehicles use a pilot bushing in place of a bearing which is a porous metal bushing saturated with oil that performs the same function.

Since the spin of the pilot bearing speeds up and slows down so rapidly when shifting, ball or needle bearings will wear out over time. When this happens the bearing must be replaced for it to function properly.

Symptoms of Faulty or Worn Out Pilot Bearings
An early sign of a failing pilot bearing is a chirp or squeal each time the clutch is engaged or disengaged.

Symptoms of completely failed pilot bearings include:

• The transmission jumping out of gear or not being able to be put in gear
• Severe vibrations coming from the rear of the engine
• No engagement of the clutch
• Catastrophic failure of the engine or transmission (in extreme cases)

Replacing Your Porsche Pilot Bearing
The pilot bearing can be removed and replaced by removing the transmission and clutch and using a bearing puller to remove the pilot bearing from the end of the crankshaft or flywheel.

It is recommended to replace the pilot bearing or bushing when the clutch is replaced and a new pilot bearing is often supplied along with the clutch in most clutch kits on the market.

Porsche Pilot Bearings.