What is Clutch Clearance?
2 Answers
Clutch clearance refers to the gap between the front and rear end faces of the driven disc and the surfaces of the flywheel and pressure plate after the clutch is disengaged. The free travel of the clutch pedal refers to the pedal travel from when the clutch pedal is depressed until the free clearance is eliminated. When the clutch is depressed, under the action of the clutch spring, a gap forms between the flywheel, friction disc, and clutch. As the clutch is slowly released, this gap gradually decreases until complete engagement is achieved. The power of the vehicle is transmitted through the friction between the engine flywheel and the clutch. When the car engine is running, the flywheel rotates with the engine, but since the transmission is in neutral, the vehicle's transmission does not transfer power to the chassis, and the car does not start or move. When the clutch is depressed, a gear is engaged, and the clutch is slowly released, the vehicle will start and move.
The clutch clearance refers to the gap when the clutch is engaged, especially common in manual transmission vehicles. With decades of repair experience, I've seen countless cases where too little clearance leads to premature clutch wear and difficulty shifting gears, while excessive clearance causes noise or slippage during gear changes. Last week, a young man brought in an old Jetta with severe clutch shudder. Upon inspection, I found the clearance was less than half a millimeter. Adjusting it to the standard 2-3 mm resolved the issue. This is crucial because it directly affects power transmission efficiency and component lifespan. I recommend adjusting it every 20,000 km using the adjustment screw to avoid costly repairs later. Even with modern electronic systems in new cars, the principle remains the same—always ensure the pedal rebounds smoothly before driving.
