When the computer decides that the time is correct, it disengages the clutch automatically, selects a different gear and after that re-engages the clutch. The stress on the ATF is controlled by a governor connected to the output shaft, which differs the force according to the car or truck velocity. https://gearboxauto28394.diowebhost.com/89121137/the-definitive-guide-to-gearbox-auto