As part of the front and/or rear axle assembly, the differential plays an integral role in how your car makes turns. The differential is designed to drive a pair of wheels while allowing them to rotate at different speeds. This function provides proportional RPMs between the left and right wheels. If the inside tire rotates 15 RPM less in a turn than going straight, then, the outside tire will rotate 15 RPM more than going straight.

For example, when your vehicle goes around a corner, the wheel on the outside must travel faster than the wheel on the inside. The differential distributes equal amounts of torque to both wheels. This permits the wheels to react to resistance, or provide traction, to give the wheel more resistance to rotate less. The wheel with less resistance rotates faster.

Some vehicles, such as go-karts, are not equipped with a differential. In this case, both driving wheels are forced to rotate at the same speed, usually on a common axle driven by a simple chain-drive apparatus. Front wheel drive vehicles are designed differently in that the axle and differential assembly is located in the transmission axle assembly or transaxle.