The primary automatic transmission to work with a torque converter (in lieu of a fluid coupling) was the Buick Dynaflow, which was introduced to the 1948 product year. In normal driving, the Dynaflow employed only the leading equipment, counting on the torque multiplication from the torque convertor at decrease speeds. https://andypvwws.mybuzzblog.com/13869513/detailed-notes-on-gearbox-auto