Oil leakage of a clutch slave cylinder is most possibly caused by wear of a piston, leather collar, or leather cup that prevents normal sealing of clutch oil:
- During operation of the slave cylinder, the release yoke disengages the clutch pressure plate and the disc from the flying wheel, thus allowing gear shifting;
- After the clutch is released, the slave cylinder ceases to work. The clutch pressure plate and the disc contact the flying wheel to restore power transmission, and the oil will flow back from the slave cylinder to the oil tank;
- In the case of difficult gear switching and incomplete disengagement, the clutch master cylinder and the slave cylinder should be checked for any sign of oil leakage. Any problem discovered should be fixed in time. Appropriate measures should be taken to reduce wear. Other inspections should be performed as well if necessary.

Name: clutch slave cylinder
Ref No. : 6QE721261
Applicable models:
Skoda: FAB00-15/FABI09-14/OCT04-13/RAPI12-/RO06-15/SUP08-13/YET10-13
VW: BO03-05/CA04-15/EOS06-11/FO05-12/FOA04-10/GL09-11/GOLF03-11/GOPL05-11/JE06-11/LU99-06/PA06-15/PO02-15/SA12-13/SCI09-14/TOUO03-15
Seat: ALT04-10/CO03-05/IB06-11/LE06-10
Audi: A1 11-14/A3 04-13/A3CA08-13