A clutch release bearing, popularly known as a “throwout bearing”, is a component of the clutch assembly in a manual transmission system.
In order to effectively switch between gears in your manual transmission, it is necessary to momentarily disengage the transmission from the engine. That is the job of the clutch. The clutch is located between the engine and the transmission and connects the engine crankshaft to the transmission input shaft.
When the clutch is disengaged (when you press the clutch pedal), the engine and transmission operate independently of one another. But when you let out the pedal and the clutch is engaged, friction between the clutch pressure plate and the clutch disc allows the crankshaft and transmission input shaft to be connected and spin at the same speed.
The clutch release bearing reacts to force from the clutch slave cylinder when you press the pedal to disengage the clutch.
Most technicians will advise that all of the components of a clutch assembly should be replaced at the same time. This is for a couple of reasons. First of all, the time that it takes to replace one of the components of a clutch is essentially the same for replacement of the entire assembly. It is also likely that, if one component is worn, the other components are in a similar condition. Therefore, it is common to replace the clutch disc, pressure plate, and pilot bearing along with the release bearing.
To replace a clutch release bearing, a technician must first safely lift and support your vehicle in the air for access. From there, a typical clutch assembly replacement consists of the following: