The very first automatic transmission to employ a torque converter (in lieu of a fluid coupling) was the Buick Dynaflow, which was released for that 1948 model year. In standard driving, the Dynaflow employed only the top equipment, counting on the torque multiplication with the torque convertor at decreased speeds. https://emiliobsfsf.blogitright.com/33917421/the-fact-about-gearbox-auto-that-no-one-is-suggesting