The very first automatic transmission to work with a torque converter (instead of a fluid coupling) was the Buick Dynaflow, which was launched for that 1948 design yr. In usual driving, the Dynaflow applied only the leading gear, relying on the torque multiplication of the torque convertor at lessen speeds. https://raymondmonll.blogdeazar.com/33952489/5-easy-facts-about-gearbox-auto-described