by Paul Novak
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The clutch in a car is made up of several components that must work together for the clutch assembly to function properly. The clutch assembly is the direct link between the engine and the transmission and is responsible for transferring power to the rear wheels of the vehicle. As such, problems like a worn clutch thrust bearing can produce pronounced symptoms indicating that service is required.
A worn thrust bearing has more clearance between its rollers. This allows the bearing to move excessively in its seat, which can lead to rattling, squealing, or grunting coming from the transmission. These noises are usually most noticeable when the clutch pedal is depressed to release the clutch.
Pedal vibration / pulsation
When a vibration is felt while pressing the clutch pedal, it may indicate a worn thrust bearing. While the pedal is depressed, the worn bearing cannot evenly distribute the load on the clutch plate, causing uneven contact with the pressure plate and the resulting vibration or pulsation felt on the pedal.
Thrust bearings can lose their lubrication over time as they wear. This lack of lubrication can cause the bearing to move stiffly or bind, making it difficult to fully disengage the clutch during shifting. This can cause grinding directly due to lack of lubrication in the bearing, and grinding from attempting to shift gears while the bearing is not fully releasing the clutch. The end result is the difficulty of getting the transmission to shift gears.