The main automatic transmission to utilize a torque converter (in lieu of a fluid coupling) was the Buick Dynaflow, which was introduced to the 1948 design calendar year. In normal driving, the Dynaflow employed just the major equipment, depending on the torque multiplication with the torque convertor at reduced speeds. https://martinrcgjj.sharebyblog.com/33974558/the-5-second-trick-for-gearbox-auto