What is the function of an automatic transmission valve?
2 Answers
The function of the valve body on the transmission is to perform high and low gear shifts. When the vehicle speed reaches a certain gear speed, the hydraulic oil pushes the valve body to automatically shift the gear to the corresponding position. Here is additional information: 1. The automatic transmission can automatically change the transmission ratio based on engine load and vehicle speed. 2. The automatic transmission is easy to operate and can significantly improve the safety and reliability of vehicle driving in congested traffic. 3. Currently, passenger cars widely use a single-stage, two-phase, three-component lock-up type integrated hydraulic torque converter composed of a pump wheel, turbine, and guide wheel. 4. After the engine starts, the crankshaft drives the pump wheel to rotate. The centrifugal force generated by the rotation causes the working fluid between the pump wheel blades to be thrown from the inner edge to the outer edge along the blades. This working fluid has both a circumferential component speed that rotates with the pump wheel and an axial component speed that rushes toward the turbine.
The automatic transmission valve body is a complex system where various valves act like commanders, managing hydraulic pressure flow to ensure smooth gear shifts at different speeds. The pressure regulator maintains proper pressure, while the shift control valve responds to computer commands to quickly switch gear positions. I frequently handle such repair cases and find that once valves age or accumulate dirt, the car may experience delayed shifting, strong jerking sensations, or even slipping and stalling. In severe cases, shifting may fail, leading to costly transmission overhauls. To prevent this, I recommend replacing the transmission fluid with a high-quality type every 50,000 kilometers and regularly inspecting the valve body condition. This maintains smooth driving and extends transmission life by over a decade. Neglecting maintenance can result in expensive repair bills—I've seen owners spend thousands fixing valve issues.
