How Many Differentials Does a Semi Truck Have?

A semi truck typically has two differentials. The front and rear differentials are the two primary components of the truck’s drivetrain.

They serve to transfer power from the engine to the wheels, allowing the truck to move forward or backward.

The front differential is located between the engine and transmission, while the rear differential is located between the transmission and wheel axles. The front differential works by transferring power from the engine to the transmission, where it is then sent to either side of the wheel axles for power distribution. The rear differential works by taking power from both sides of the wheel axles and sending it to both wheels simultaneously, providing a balanced movement for both wheels.

The differentials also help with cornering and maneuverability by allowing each wheel to rotate at a different speed than its counterpart when turning. This helps keep tires from slipping and provides a smoother ride as well as improved fuel efficiency.

Differential Types

There are several types of differentials that may be used in semi trucks. The traditional open differential is the most common type used in most semi trucks, however there are some specialty trucks that use other types such as limited-slip or locking differentials.

Open differentials are best suited for general purpose use, while limited-slip or locking differentials may be necessary for off-road applications.


Semi trucks typically have two differentials – one in front and one in back – which help transfer power from the engine to the wheels for forward or backward movement. Differential types vary depending on application but open differentials are usually found in most semi trucks. Differential technology helps improve fuel efficiency and provides better handling when cornering or maneuvering.

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James Gardner