The initial automatic transmission to implement a torque converter (instead of a fluid coupling) was the Buick Dynaflow, which was released for that 1948 design yr. In ordinary driving, the Dynaflow made use of just the prime equipment, relying on the torque multiplication of your torque convertor at decrease speeds. https://brooksrzgmq.blogmazing.com/32951968/gearbox-auto-an-overview