What happens when a clutch master cylinder fails?

When a clutch master cylinder fails, one of several things can occur. The clutch pedal may become abnormally easy or difficult to press. You may have difficulty shifting from neutral into a gear, or difficulty shifting in and out of any gears. The short answer is, you may not be able to shift gears to drive your vehicle at all.

What causes clutch master cylinder failure?

Clutch master cylinder failure is typically caused by moisture buildup inside the master cylinder. Brake fluid naturally attracts water vapor and can lead to corrosion of the master cylinder from the inside out. Corrosion then leads to the piston sticking and/or not sealing properly, which causes leaks and loss of pressure and therefore failure of the clutch master cylinder.

Why does my clutch pedal go all the way to the floor?

If your clutch pedal is going all the way to the floor, you may have a clutch master cylinder that's low on fluid, has blown seals on the piston, or your vehicle may have a leak in the clutch hydraulic line. If, by chance, your vehicle has a mechanical clutch, then the mechanical linkage or clutch cable may be broken or may have come loose.