The 1st automatic transmission to work with a torque converter (as opposed to a fluid coupling) was the Buick Dynaflow, which was launched for that 1948 design yr. In typical driving, the Dynaflow utilized only the prime equipment, counting on the torque multiplication from the torque convertor at reduced speeds. https://elliottwwusq.bloggadores.com/33004035/helping-the-others-realize-the-advantages-of-gearbox-auto