General information about the clutch (Audi A8 D2)

The clutch is located between the engine and the gearbox and is designed for short-term disconnection and smooth connection of the engine crankshaft and the gearbox input shaft when the car starts moving and during gear shifting without noise and risk of damage to parts.

All models are equipped with a dry single-disc clutch, which consists of a driven and pressure clutch disc, a central diaphragm spring, a casing and a clutch release bearing.

Clutch slave disc moves freely on the splines of the primary shaft of the gearbox and is clamped between the flywheel and the pressure plate by the force created by the central diaphragm spring. Friction linings are riveted to both sides of the driven disk. Clutch slave disc is connected to the hub through the torsional vibration damper parts. The need for a torsional vibration damper is caused by the following.

When the vehicle's speed changes abruptly, when it hits uneven road surfaces, when the clutch is suddenly engaged, or as a result of uneven engine operation, dynamic loads arise in the vehicle's transmission, causing twisting (unwinding) transmission shafts. Uneven engine torque can cause significant overloads in the transmission due to the occurrence of torsional vibrations and resonance when the frequencies of the transmitted loads coincide with the frequencies of the natural vibrations of the transmission. Elastic vibrations of the transmission lead not only to the occurrence of noise in the mechanisms and units, but also to dangerous vibrations, and sometimes to breakdowns of parts when the amplitude of vibrations reaches a large value. The energy of torsional vibrations is absorbed by the damper.

The clutch release drive is hydraulic. The clutch release bearing is mounted on the front side of the gearbox on the clutch release sleeve. The bearing is moved by the clutch release fork. When the clutch pedal is pressed, the piston in the master cylinder moves and compresses the fluid, which flows through the hose into the clutch slave cylinder. Under pressure, the piston of the clutch slave cylinder moves, actuating the clutch release fork. The clutch release fork moves the bearing, which acts on the spring of the pressure plate and moves the pressure plate away from the slave disk of the clutch. The clutch is adjusted automatically.