Clutch troubleshooting usually comes down to identifying the location of the problem. Knowing what to look for when a certain action happens can help you diagnose the clutch problem, and may save you money at the repair shop. Whenever you take your car in for service, remember that providing detailed information to your mechanic will help you get quick and complete repairs.
If the clutch pedal travels to the floor with very little or no resistance, the clutch's master or slave cylinder is bad. The seals and hoses to the cylinders leak over time, and the cylinders must be replaced.
Another cause may be a leaky hose or fitting. Check all hoses and fittings for leaks. One sign of leaks a drop in the fluid level in the master reservoir. You may also see drips under your car. Put a piece of white cardboard or poster board under the car while it's parked, then look directly above the drips to find the location of leaks.
A broken clutch release lever can also cause softness in the pedal. You can examine the clutch release lever by looking at the end of the lever in the opening in the clutch housing. If it moves easily, it's probably broken.
Slips and Failure to Shift
If the vehicle will not go into gear, you may have a bad clutch disc or a bad pressure plate. The transmission or shift linkage may also be worn out. If you have a bad clutch disc or pressure plate, the clutch needs to be replaced. If the shift linkage is bad, it can be rebuilt.
If the transmission is bad, it must be rebuilt or replaced. Check prices for both. Replacing the transmission is sometimes cheaper than rebuilding the transmission, especially on newer cars.
If the clutch slips, you could have a bad clutch disc, or the pressure plate or flywheel may be warped. If the clutch disc is bad, the clutch needs to be replaced. When replacing the clutch, check the flywheel for signs of warping. A leaky rear main seal in the engine may cause the clutch to become contaminated. If this is the case, replace the rear main seal and the clutch.
Heavy-duty clutch use, such as when you're towing or racing, may also cause the clutch to slip. This is usually caused by overheating. Let the clutch cool for about an hour. It should stop slipping. Remove what you're towing and see if the clutch operates normally. If it does, you know that towing is the source of the problem.
If there is a noise or vibration coming from the clutch, the throwout bearing or pilot bearing may be warn out. A broken spring in the clutch plate will also cause noise and vibration.
Replace the bearings if they're worn. You may want to replace the clutch and the front seal at the same time, because the transmission must be pulled out to change the bearings. Removing the transmission is costly, so it makes sense to complete as much routine maintenance as possible while it's out.
Bleeding a clutch can be a real chore for some vehicles. Get tips for bench bleeding and working air out of the transmission system.
How much does it cost to replace a clutch? Well, that depends on a lot of things, not least of which is what kind of car you drive.