The first automatic transmission to use a torque converter (as opposed to a fluid coupling) was the Buick Dynaflow, which was released for the 1948 product calendar year. In ordinary driving, the Dynaflow made use of only the top equipment, counting on the torque multiplication from the torque convertor at https://dantexfghi.blogminds.com/gearbox-auto-can-be-fun-for-anyone-31286528