According to the role of the axle, the axle can be divided into: steering axle, drive axle, support axle and steering axle.
Steering axle: The front axle of the truck is a steering axle. The structure of the steering axle is basically the same, consisting of a front axle, a steering knuckle, a kingpin, and a wheel hub.
Drive axle: A bridge that provides power to a truck. Rear-wheel drive models generally have two forms of single-wheel drive and two-wheel drive.
Support bridge: there is no power output, only the bearing function. Some single-axle-driven three-axle vehicles (6X2 cars) have a support bridge in the middle or rear axle, and the axles on the trailer are all support bridges.
There is also a suspension bridge form in the support bridge. Suspension bridge refers to a bridge that can float up and down. The structure is basically similar to ordinary support bridges. An additional lifting mechanism is added to lower the suspension bridge when the truck is under heavy load to carry the weight. The no-load or light load is to increase the suspension bridge to reduce fuel consumption.