The Ford AOD automatic overdrive four-speed transmission, introduced in 1980, was used with most Ford engines of the day. Ford later introduced the AODE, a computer-controlled version of the AOD. The AODE was used from 1992 to 1995, when it was improved with wider gear ratios to become the 4R70W. The AODE and 4R70W differ from the older AOD by an attached cable, allowing computer control. The AOD transmission is identified visually, first to identify the AOD, then to differentiate between the AODE and 4R70W transmission.
Slide under the vehicle to view the transmission pan. The transmission is under the center of the vehicle, immediately behind the engine. The pan is located on the bottom of the transmission and attached by 14 bolts.