Manual Transmission Clutch Chatter
Clutch chatter is the initial shudder that occurs when a faulty clutch disk or clutch component first engages. This shudder or vibration may vibrate throughout the entire vehicle. It’s often the result of worn or contaminated clutch components. The clutch disc is grabbing and releasing the flywheel and pressure plate as the assembly is turning. It happens very quickly as the engine is rotating.
Clutch chatter is different than clutch slippage. Clutch chatter occurs when the clutch is first applied and goes away after the clutch has fully engaged. Clutch slippage is the continued spinning of the clutch disk without its full engagement.
Faulty dual mass flywheels, worn discs, and over machined flywheels result in clutch slippage. With clutch chatter, the vehicle shudders and shakes. With clutch slippage, the engine increases in RPM with little change in vehicle speed. Sometimes the vehicle may not even move forward.
Worn or contaminated clutch facings cause clutch chatter and grabbing. Contaminated clutch disk friction material is typically the result of oil leaking from the rear main seal or front transmission pump seal.