Assembly Plant Codes
The following table shows the plants in which the Ford trucks were made in the 1980 to 86 era. When decoding your VIN use the 5th character for 1980 trucks, or the 11th character for 1981 or later trucks, and look up that character in the table below.
Note: Ford also had a plant in San Jose, CA until 1983, and it was designated "R" as the assembly plant code. But, for some odd reason the editor(s) of Ford's Master Parts Catalog decided that they would drop that information from the last revision of the catalog in 1994. So, I've added it back.