The very first automatic transmission to implement a torque converter (in place of a fluid coupling) was the Buick Dynaflow, which was released with the 1948 product year. In ordinary driving, the Dynaflow employed only the top equipment, counting on the torque multiplication on the torque convertor at reduced speeds. https://gearbox-auto10852.bligblogging.com/34402713/about-gearbox-auto