If you're one of a handful of American drivers who still own a manual transmission vehicle, then you're probably intimately familiar with the concept of a clutch. However, you might be surprised to learn that automatic transmissions also rely on these mechanical devices. A typical automatic transmission has many clutches grouped in a component known as a clutch pack.
Clutch problems in your automatic transmission can cause various symptoms, including slippage or complete transmission failure. Understanding how they work can help you recognize the signs of trouble and, more importantly, keep your transmission well-maintained to avoid these repairs in the first place.
What Is a Clutch?
An internal combustion engine generates power by converting the linear motion of several pistons into rotational motion. Connecting rods link the pistons to a crankshaft, and the rotational movement of the shaft ultimately provides power for your car. Although many components are involved in power transmission, it's easy to see how a rotating shaft can work to turn your car's wheels.
But what if your wheels aren't moving? You don't want your engine to stop turning whenever your car stops moving, so it's necessary to disconnect the wheels and motor while idling. A clutch pedal allows the driver to disconnect input power from the engine in a manual transmission vehicle. In an automatic transmission, the torque converter handles this job without any operator input.
Your automatic transmission also includes many individual gears, and it's necessary to engage and disengage these at various speeds. Small clutch packs work to connect and disconnect each gear as required, allowing your transmission to shift as you accelerate and decelerate. These parts can fail, leading to problems shifting and total transmission failure.
Why Do Clutch Packs Fail?
The parts inside your automatic should last for the lifetime of the device, but manufacturer defects or improper maintenance can lead to premature failure. Given enough time, the individual clutches can wear out, preventing the internal gears from correctly engaging — symptoms of an internal problem such as this include slipping gears and burnt automatic transmission fluid.
You can help extend the lifespan of your clutches by not stressing your transmission. Avoid towing loads beyond your vehicle's rated tow capacity, and never drive your car if you have low transmission fluid. If you have a transmission warning light, stop driving your vehicle immediately and have a professional mechanic perform a thorough evaluation.
How Can You Fix a Failed Clutch Pack?
Automatic transmissions are often too complex to replace individual parts. When a clutch pack fails, a complete repair usually involves rebuilding the transmission and replacing multiple clutches, bands, seals, and other internal components. Since rebuilds can be expensive, this approach ensures that your transmission will last you for thousands of additional miles instead of shortly failing again.
If your transmission is struggling, contact a transmission service in your area.