Manual Transmission Clutch Chatter
Clutch chatter is the sudden shudder that occurs when a faulty clutch disk or clutch component is initially engaged. This shudder or vibration may vibrate throughout the entire vehicle. It’s often the result of worn or contaminated clutch components. This chatter is caused by the disc 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 and worn or over machined flywheels result in clutch slippage. With clutch chatter, the vehicle will shudder and shake, and with clutch slippage, the engine increases in rpm with little change in vehicle speed. If it’s real bad, 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 a leaking crankshaft main seal or front transmission seal. Depending on the vehicle, this oil may easily be seen during a visual inspection of the clutch housing.