Chang' an automatic gear, step on the brake, and the gear machine becomes louder.

The vibration of automatic gear shifting is relatively large and the shifting speed is relatively slow, indicating that it is time to change the oil in the gearbox.

There is a normal sound phenomenon. Look at how many parts the automatic gearbox shifts, and you will know why the sound is loud.

The working principle of AT automatic transmission system can be simply expressed as follows: the ECU of automatic transmission controls the main oil pressure regulating valve and gear solenoid valve of the actuator according to the signals of engine speed sensor, throttle position sensor, accelerator pedal sensor, transmission gear switch and gear sensor;

The main oil pressure regulating valve and the shift solenoid valve control the corresponding clutch, brake and other shift actuators by changing the oil pressure and controlling the oil circuit; Clutch and brake control planetary gear mechanism to realize automatic switching between forward gear and constant speed gear.