The main automatic transmission to make use of a torque converter (as an alternative to a fluid coupling) was the Buick Dynaflow, which was released with the 1948 model year. In regular driving, the Dynaflow utilized only the leading gear, depending on the torque multiplication from the torque convertor at https://gearboxauto19741.tusblogos.com/34037441/new-step-by-step-map-for-gearbox-auto