If you readtheabovediscussiononthemanual transmission,you know the engineisconnectedthrough a clutchandmanual gearbox.Ifthere is noclutch, thenparking, thenyouhave toturn offtheengine.Butthecarwithautomatic transmissionis notclutch.It usesatorque converter. Now weneed tofind out why theautomatic transmissiontorqueconverter,thestrengths and weaknessesoftheworking principleofthetorqueconverterandtorqueconverter. Andthemanual gearbox,automatic transmissioncarsalso needtostill be able toturn thewheelandgearboxstillallowstheengine.Manual transmissionwithaclutchtodisconnecttheengineand gearbox.Theautomatic transmissionusing atorque converter.