How Many Differentials Does a Four-Wheel Drive Have?

[DiBeau]

A full-time four-wheel drive system has three differentials: one on the front axle, one on the rear axle, and a central differential between the front and rear drive shafts. The structure of a differential: It is usually integrated with the main reducer to form an assembly. The differential consists of the differential housing, left and right axle gears, planetary gears, and a cross shaft. The driven gear of the main reducer is mounted on the differential housing, forming a single unit with the differential. This entire assembly is then installed in the main reducer housing, collectively known as the main reducer assembly, commonly referred to as the rear gearbox or tail gear. The function of the differential: Firstly, it transmits power to both half-shafts. When the vehicle turns, it allows the two half-shafts to rotate at different speeds, enabling the wheels to perform unequal-distance movements in a nearly pure rolling manner. This reduces the resistance during turns and minimizes friction between the tires and the ground, thereby extending tire life. It can be said that the differential is an indispensable component in trucks.