The initial automatic transmission to employ a torque converter (in lieu of a fluid coupling) was the Buick Dynaflow, which was released for your 1948 product 12 months. In regular driving, the Dynaflow utilised just the prime gear, counting on the torque multiplication from the torque convertor at reduced speeds. https://gearbox-auto85183.tkzblog.com/33935511/details-fiction-and-gearbox-auto