The valve body on the general gearbox is used for high and low gear shift. When the vehicle speed reaches a certain gear speed, the hydraulic oil pushes the valve body to automatically shift the gear position to the gear position.
The automatic transmission can automatically change the transmission ratio according to the engine load and the vehicle speed, so that the vehicle can obtain good power and fuel economy, and reduce engine emission pollution. The automatic transmission is easy to handle, and when the vehicle is crowded, the safety and reliability of the vehicle can be greatly improved. The electronically controlled automatic transmission usually consists of a hydraulic torque converter, a planetary gear shifting system, a shifting actuator, a hydraulic operating system, and an electronic control system.