The 1st automatic transmission to implement a torque converter (rather than a fluid coupling) was the Buick Dynaflow, which was released to the 1948 model year. In standard driving, the Dynaflow made use of only the leading equipment, depending on the torque multiplication with the torque convertor at lessen speeds. https://gearbox-auto64184.answerblogs.com/34363289/top-guidelines-of-gearbox-auto