Casting and Part Numbers
Part numbers and casting numbers are pretty much the same when it comes to "hard parts". Those are those big long codes (C7ZZ-6540544-DR, etc) that you find that identify every Ford part made. Many parts are too small to have the number cast or printed on it, but it still has a casting number. These numbers tell you what that part was originally designed for, what department designed it, and when it was designed. People are often confused by looking at a part or casting number. Just because a part was originally made for a Falcon doesn't mean the part came off of a Falcon. Many Mustang parts were originally designed for the Falcon and carry a Falcon casting number. Ford is famous for using parts designed for one car on a variety of models.
A basic part number is included within the casting number and indicates what the part is, not what it was made for, or when it was made. An example could be a master cylinder - most master cylinders have a basic part number of 2140, but there a number of different master cylinders for different Ford vehicles. They all are master cylinders however, and share a basic part number.
Example for Illustrative Purposes
C5ZZ-2140-CR
C - Decade of Manufacture - 1960's in this case
5 - Decade Year - This is a '65
Z - Car line - Mustang
Z - Ford Service Part - This came from the Engineering Department
2140 - Basic part number - 2140 is a master cylinder
CR - Design Change - indicates manual disc brakes
Casting Code Definitions
Decade of Manufacture:
A = 1940
B = 1950
C = 1960
D = 1970
E = 1980
F = 1990
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