The Ford AOD transmission or "Automatic Overdrive" was introduced in 1980 and builds upon the C4 design with an added overdrive gear. The AOD is often swapped in place of the C4 on classic 60's and 70's vehicles to reduce engine wear with the added overdrive. The AOD was used in Ford F-series pickups as well as other platforms throughout the 1980's and early 1990's. Raybestos Powertrain offers OE replacement and enhanced material AOD transmission parts to increase performance. See more product details below.