The very first automatic transmission to work with a torque converter (instead of a fluid coupling) was the Buick Dynaflow, which was introduced for that 1948 product yr. In ordinary driving, the Dynaflow applied only the top gear, depending on the torque multiplication of your torque convertor at reduce speeds. https://gearbox-auto61605.worldblogged.com/39828880/how-much-you-need-to-expect-you-ll-pay-for-a-good-gearbox-auto