A torque converter in an automatic transmission takes the place of the clutch in a manual transmission. The vehicle engine must be able to move the automobile when accelerated and continue to run when stopped. The torque converter is a fluid-driven device that connects the transmission to the engine and disengages the transmission when the brakes are engaged. A variety of reasons can cause the torque converter to jerk when the gears are engaged or when changing gears.
Low Transmission Fluid
One of the main causes of the torque converter jerking during the changing of gears is low transmission fluid. Transmission turns the propeller of the torque converter. A lack of fluid does not provide the device enough power to turn the turbine, or it could make the turbine hesitate before turning, causing the torque converter to jerk. Low transmission fluid can be cause by damaged transmission seals, clogged transmission filter or thickened transmission fluid because of transmission gear debris. Once the torque converter begins to jerk, the automobile owner needs to check the fluid level to determine whether this is the cause of the torque converter jerking.
The stator of the torque converter can be damaged, which causes the torque converter to jerk when changing gears because it is not receiving enough transmission fluid. The fins on the stator can become damaged or crack over normal driving conditions. A stator freewheels during the operation of a vehicle, and this freewheeling directs transmission fluid to be pressed back into the impeller, causing the transmission to turn the wheels of the automobile. When the stator or its fins are damaged, transmission fluid is not pressed back into the impeller of the torque converter, or not enough transmission fluid is pressed back into the impeller, causing jerking during the changing of gears.
Torque Coverter Overheating
The torque converter can begin to jerk when gears are changed because the device is too hot. This overheating is caused because the torque converter is not releasing the heat fast enough and causing heat to build up inside the torque converter. Once the torque converter overheats, it damages the elastomer seals and begins to leak large quantities of transmission fluid out of the torque converter. Once transmission fluid leaks out of the torque converter, the automobile will begin to jerk during the changing of gears. The torque converter must be replaced because the elastomer seals is not the problem, the overheating is the problem.