A thrust support is a particular type of rotary bearing. Like other bearings they permanently rotate between parts, but they are designed to support a predominantly axial load.

What does a camshaft thrust support do?

When using a roller cam you need to provide some means of holding the cam back to the rear of the engine. Cam thrust button rides between the front of the timing gear and the back of the front cover for proper end play in the cam.

What happens when a thrust bearing fails?

If there's too little thrust clearance, the thrust bearing surfaces can't maintain a sufficient oil film and will overheat and be destroyed, potentially allowing the crankshaft's main journal fillets to walk into the saddle and cap areas, quickly resulting in severe crank damage.

How do I know if my thrust bearing is bad?

A worn thrust bearing has increased clearances between its rollers. This allows the bearing to move around in its seat excessively, which can lead to rattling, squealing or growling noises coming from the transmission. These noises are usually most noticeable when the clutch pedal is pressed down to release the clutch.

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