The 1st automatic transmission to utilize a torque converter (instead of a fluid coupling) was the Buick Dynaflow, which was launched with the 1948 design calendar year. In regular driving, the Dynaflow applied just the top rated gear, counting on the torque multiplication of your torque convertor at decrease speeds. https://gearboxauto31728.madmouseblog.com/14634872/not-known-details-about-gearbox-auto