Symptoms of a Failing Clutch Slave Cylinder

The clutch slave cylinder is a key component of your car’s powertrain, which includes the engine, the transmission, and the other related parts that get the power to the ground. The powertrain is very important to your car’s acceleration, shifting, and cruising, so it is essential that your clutch slave cylinder is in good operating condition at all times.

The clutch slave cylinder receives the hydraulic pressure generated by the clutch master cylinder. When the clutch pedal is depressed, the slave cylinder disengages the clutch, which allows the manual transmission to be shifted into the desired gear. The slave cylinder also forces the clutch pedal to return to the raised position when released. While some clutch slave cylinders are mounted on the outside of the manual transmission, others are located inside the transmission.

If your car has a manual transmission, it most likely has a clutch slave cylinder. If your car has an automatic transmission, it does not have a clutch slave cylinder.

Symptoms of a bad clutch slave cylinder

A problem with your clutch slave cylinder can be very dangerous. Because your clutch slave cylinder permits the proper shifting of your manual transmission, your ability to control your vehicle’s power can be affected. A bad clutch slave cylinder could potentially cause a loss of power to the wheels and result in an accident. Many factors can cause wear to and deterioration of your clutch slave cylinder. Here are some of the warning signs of a bad clutch slave cylinder:

• Clutch does not work
• Clutch pedal sinks to the floor
• Clutch pedal feels spongy, soft, or loose
• Clutch pedal feels hard
• Gears grind while shifting
• Gears are hard to shift
• Gears will not shift
• Clutch fluid low and/or leaking
• Engine stalls because car cannot be shifted out of gear when stopping
• Squeaking sound when clutch is depressed
• Brake fluid is contaminated (dark or cloudy appearance)
• Brake fluid leaks onto floor around clutch pedal

Repairing a bad clutch slave cylinder

A bad clutch slave cylinder usually has failed due to either wear and tear or damage, so replacement with a new clutch slave cylinder is the standard solution. Because the clutch slave cylinder is an integral part of your car’s powertrain, it must be repaired before you can drive your car again. If you have the type of clutch slave cylinder that is located inside your car’s transmission, replacing it will involve removing the transmission to access the bad clutch slave cylinder, so a significant amount of labor will be involved, if that is the case.

After confirming the need to replace the clutch slave cylinder, your mechanic will access the bad clutch slave cylinder (and remove the transmission if necessary). Next comes removal of the bad clutch slave cylinder, replacement with a new one, and then reinstallation of the transmission into your vehicle if needed. Your mechanic will probably replace your clutch master cylinder at the same time, since it is likely to be just as worn as the clutch slave cylinder. The hydraulic system will then be flushed, refilled and bled, and then tested for proper operation.

Don’t try to repair a bad clutch slave cylinder yourself

Unless you have had extensive experience in working with manual transmissions and hydraulic systems, leave this to the professionals! Your clutch slave cylinder must be installed correctly, with fresh hydraulic fluid and no air bubbles in the lines. If the repair is not done properly, you will have the potential for some serious driveability problems or transmission damage. Your mechanic has the proper tools and equipment to replace your clutch slave cylinder safely and efficiently.