The only time most people think about their vehicle's drivetrain is when they hear funny noises, have leaks or have difficulty shifting. Most people believe any of these problems automatically mean an expensive repair bill. By learning more about your vehicle and getting to know your ASE-certified service technician, you can eliminate many causes for worry. Remember, regular service and maintenance lead to fewer and less expensive repairs. Do you have front or rear wheel drive? A vehicle equipped with front wheel drive has the engine, transmission and differential combined into one unit. A rear wheel drive vehicle transfers power from the engine to the rear wheels through the transmission and drive shaft. The following is a list of the drivetrain components: Clutch or torque convertor Manual transmissions are equipped with a clutch while automatic transmissions have a torque convertor. These components transfer power to the transmission from the engine, and allow the vehicle to stop without killing the engine. CV (Constant Velocity) Joints CV Joints allow wheel movement to steer the vehicle, provide the wheels with the flexibility to move over bumps and transfer power from the drive shafts or axles to the wheels. Differential The differential is located near the center of the rear axle housing. It transmits power to the wheels through the individual axles and allows the wheels to rotate at different speeds during turning. Drive shaft The transmission and differential are connected by this shaft.

Transaxle To decrease vehicle weight and increase passenger space, many vehicles have a combined unit of the transmission and the differential. Transmission In both front and rear wheel drive, the transmission is the shifting component. Based upon road speed and load, the transmission provides the correct gear ratio for engine performance and economy. Universal Joints The universal joints on the drive shaft of rear wheel drive vehicle give flexibility between the transmission and differential so the axle housing may move with road irregularities. Today's transmissions are increasingly complicated, therefore, the technicians specializing in transmission service must be more highly skilled than ever before. To keep up with the rapidly changing technology used in transmissions, technicians subscribe to technical information services, study technical manuals and publications produced by manufacturers, and attended technical educational seminars. As a consumer, you have the right to see proof of training and certification. ASE certified technicians can offer you suggestions on how to keep your transmission in top working order. Qualified technicians recommend your transmission fluid and filter be changed every 15,000-18,000 miles if you drive under severe conditions. Severe conditions are defined as driving on hills or mountain, in stop and go traffic, on snow or ice, while towing a trailer or boat, and 15,000 or more miles a year. To ensure proper service of your vehicle's drivetrain and for more specific service intervals for your particular vehicle, consult your ASE certified service technician and your owner's manual.