Standard (manual) transmissions and clutches have existed since the invention of the automobile over 100 years ago. Billions of such gearboxes and clutches have been manufactured and serviced in this time. Motor vehicles with standard transmissions depend on a clutch to decouple the engine from the rear wheels when the vehicle is stopped (or the engine would stall) and to enable smooth shifting when the vehicle is rolling. The problems with standard transmissions and clutches are well known and very straightforward to diagnose and repair.

You may be experiencing any of the following problems with your vehicle’s standard transmission and clutch.

Clutch Slippage

Clutch slippage might just be due to improper clutch linkage adjustment. However, the most common causes of clutch slippage are a worn clutch disc and a clutch pressure plate whose springs have been weakened by time and heat. These parts should always be replaced together with a new clutch release bearing when the vehicle’s transmission is removed. In addition, the engine’s flywheel, to which the clutch attaches, may need resurfacing.

Another common cause of a slipping clutch is a leaking rear main crankshaft seal on the engine that lets oil into the clutch housing. This seal can be replaced while the transmission is removed to replace the clutch.

Clutch Chatter

This problem could be caused by any number of things including: your engine’s flywheel might need to be resurfaced, or there might be oil on your clutch plate lining, or the lining could have become glazed. Bad engine or transmission mounts or improper clutch linkage adjustment may also contribute to clutch chattering.

Clutch Does Not Release

Usually, this problem is caused by improperly adjusted clutch linkage or from the fluid level in the clutch’s hydraulic release system being low. It may also be that the clutch’s master cylinder and/or hydraulic slave cylinder needs replacement.

Clutch Makes Noises When the Clutch Pedal Is Depressed

Usually, this is a sign of a worn clutch release bearing. Or, the pilot bearing for the transmission input shaft in the end of the flywheel could be worn out, or the transmission input shaft bearing could be faulty.

Clutch Pedal Feels Too Stiff

This could be from a worn out clutch release fork, or an unlubricated clutch release mechanism.

Sound clutches are critical to the smooth operation and long life of your vehicle’s standard transmission. National Transmission can quickly evaluate your vehicle with regard to any clutch problem and give you a firm estimate on repairing whatever is wrong. Remember that diagnosis by our expert technicians is free.