The Ford Automatic Overdrive (AOD) is a new concept four-speed automatic transmission that incorporates a new fuel-efficient torque converter, split torque in third gear and a full mechanical drive in fourth (overdrive).
In third gear, forty per cent of the power is transmitted hydrodynamically; the other sixty per cent is transmitted mechanically by direct connection between the engine and transmission.
In overdrive, engine power completely bypasses the torque converter and follows a direct mechanical path to the driveshaft.
The AOD is available in 1980 Lincoln Continental, Continental Mark VI, Ford, Mercury, Thunderbird and Cougar XR-7 vehicles.