How to Identify Ford Automatic Transmissions

by Floyd Drake III
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Many automatic transmissions have been used by the Ford Motor Company throughout the years, from early Ford and Cruise-O-Matic's to automatic overdrive four-speeds transmissions.The C-series' are Ford's primary automatic transmissions and are evolutionary, with the C3, C4 and C6 models each having an improvement on the last. All are visually identifiable, with other methods reserved for in-depth identification, such as year of production. The prime identification source is the pan located on the bottom of the transmission; its shape and bolt count is indicative of which model transmission is present.

Step 1

Inspect the pan found on the bottom of the transmission. According tio Kelly Hot Rod, many Ford Automatic transmissions, especially the C-series, can be identified by the bottom pan shape and the bolt count. All of the C-series' transmissions essentially have square pans, however, the C3 has a recess on the rear passenger side, the C4 has a bulge on the front passenger side corner, while the C6 has a recess on the rear passenger side that faces the rear of the vehicle. The Ford-O-Matic has a square pan with no recess.

Step 2

Count the number of bolts on the transmission pan. Kelly Hotrod identifies the following bolt counts: the C3 has 13 bolts, the C4 has 11 and the C6 has 14. Charlie's Transmissions Ford-O-Matic page lists 15 bolts for the Ford-O-Matic.

Step 3

Identify Ford Automatic Overdrive (AOD) transmissions. identifies four different variations of this four-speed first introduced in 1988. Each has a different pan shape, while two versions have the same bolt count. Use a combination of the two to identify the transmission. First, compare the pan shape to the gasket chart on Fordification's four-speed automatic chart, then count the bolts. A4LD, 4R44E and 4R55E transmissions have 18 bolts, AOD, AODE and 4R70W transmissions have 14 bolts, and the large, heavy-duty E4OD and 4R100 transmissions each have 20 bolts.

Step 4

Identify the Cruise-O-Matic transmission's visual characteristics. notes the use of a cast-iron case, unlike other Ford three-speed automatics. It also has a separate aluminum bell housing and extension housing bolted to it.

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