Mercedes-Benz W124 clutch: pedal stays down and judder
The W124 clutch pedal stays down or the clutch does not release properly. What is wrong?
The most common cause is a fluid leak: the clutch fluid level is too low or the slave cylinder (on the side of the gearbox) lets the fluid past. The master cylinder may also be worn. If the fluid is old, replace it (DOT 4) and check both cylinders.
Why does the W124 judder when pulling away and changing gear?
The cause is often tired damper springs in the middle of the clutch disc, in which case the disc needs to be replaced. Other causes are worn rubber joints in the propshaft, worn engine and gearbox mounts, and worn or unbalanced tyres. On the diesel, the shock damper in the throttle linkage has reduced jerking.
There is a rumble or a clunk near the W124 clutch. What causes it?
The rumble often comes from wear at the front end of the propshaft, from the mounts or from a bearing. A broken lug on the gearbox mount can cause vibration and a clunk when the clutch is released. A bang when changing gear can be caused by a badly worn clutch disc.