Car Transmission and Drivetrain Systems

Upkeep of your transmission may save you money in the long run. Learn manual and automatic transmission basics, then move on to clutches, differentials and torque converters.


You've proudly driven a stick shift all your life, so you already know that manual transmissions accelerate faster than automatics. End of story. Well, that was once true, but things have changed.

Manual transmission synchronizers are devices that eliminate the need for double clutching when changing gears. Learn how manual transmission synchronizers work in this article.

You find liquid leaking from your car and are at a loss about what to do. Learn about how to identify a transmission fluid leak in this article.

Manual, automatic, sequential, dual-clutch -- these are just a sample of what you'll see in this image gallery. Check out pictures of all types of transmissions right here.

You probably know that any car with a manual transmission has a clutch -- it connects and disconnects the engine and transmission. But did you know that automatics have clutches, too?

Most people know that cars come with two basic transmission types: manuals and automatics. But there's also something in between that offers the best of both worlds -- the dual-clutch transmission. Check it out.

Traction control helps limit tire slip in acceleration on slippery surfaces. Many of today's vehicles employ electronic controls to limit power delivery for the driver, eliminating wheel slip and helping the driver accelerate under control.

In a regular transmission the gears are literal gears -- interlocking toothed wheels. Continuously variable transmissions, on the other hand, don't have interlocking gears. The most common type operates on a pulley system. Learn all about the smooth-operating ultra-efficient CVT.

Combine the ease of an automatic with the driver control of a manual and what you've got is a sequential manual transmission. A simple forward push advances the gear. Learn all about the sequential gearbox.

Both automatic and manual transmissions accomplish exactly the same thing, but they do it in totally different ways. And it turns out that the way an automatic transmission does it is pretty amazing!

Manual transmissions use mostly helical gears, but reverse is a special situation that requires a different type of gear -- a spur gear. Learn why a spur gear makes a loud whirring noise when the car's in reverse.

Car wheels spin at different speeds, especially when turning. The differential is what lets a car make turns with ease. Find out how this key component allows the wheels to rotate at different speeds.

I see many dump trucks with wheels on two rear axles on the ground and a third axle with elevated wheels that can be lowered. These seem to be used when the truck is full -- but why include what must be expensive hardware to raise and lower the wheels? Why not just keep them down at all times?

Gear ratios are what allow a car to reach a high rate of speed or climb a steep hill. Learn about gear ratios, gear trains and planetary gear systems.

What does that funny "H" pattern on my car's gear shift have to do with my transmission? How does it make the car change gears? And when I mess up and hear that horrible grinding sound, what is actually grinding?