The transmission is the collection of mechanisms that carry torque from the engine to a car’s wheels, making it move.
The transmission’s main jobs:
- Changing the drive force and the wheels’ rotational speed.
- Enabling forward and reverse motion.
- Disconnecting the engine from the drive wheels when needed.
The transmission’s main components: the clutch, gearbox, driveshaft, final drive and differential, and axle shafts.
These are usually located under the body. That’s why the first thing you see on a flipped-over car is the transmission components.