How to Read a Ford Block Date Code

Ford uses a broad range of numbering structures for their date codes. Most of the block date codes you see will have nine digits in three different group types. Once you understand how the structures work, you can read and understand the codes easily. Knowing how to read Ford block date codes will help you if you need to match a number block when restoring an old Ford, for instance. Knowing the correct age of a part will help you know whether you've found an identical part to replace it.

1. Locate the date code stamped on the right side of the Ford block

Locate the date code stamped on the right side of the Ford block, just above the starter on Boss 302, 351W/351C and 221/260/289/302 engines. The date code can also be on any machined surface of the block and will have four alphanumeric digits, such as "5E30." This number represents the assembly date if stamped on the machined boss; otherwise, you will see a metal tag or decal. Use the stamped production date whenever possible for reference, since you can find it more easily, and because the decal or label can be missing.

2. Find the decade of the date by looking at the first letter of the part number

Find the decade of the date by looking at the first letter of the part number, also located above the starter, eight or more digits long separated by hyphens or spaces. For example, for the 1950s, the first letter would be "B," then the letter "C" for the 1960s, "D" for the 1970s, "E" for the 1980s, "F" for the 1990s and so forth. A Ford part number can look like, "F6TE-2002," showing a 1990s decade.

3. Look at the first digit of the Ford block date code

Look at the first digit of the Ford block date code, which appears like a four-digit code, sometimes with a fifth digit representing the engine size or horsepower. The first number represents the decade year. For this example, in a four-digit code of "5E30", "5" means 1995 when appearing as the first digit.

4. Read the second digit, representing the month and alphabet position

Read the second digit, representing the month and alphabet position. Ford does not use the letter "I" in this case. The letters can be an "A" for January through "M" for the month of December. The "E" as the second digit, for instance, means the fifth month, or May. An "H" in this position would mean the month of August, as the eighth letter of the alphabet.

5. Interpret the third and fourth digits as the day of the month

Interpret the third and fourth digits as the day of the month. For instance, "30" in the third and fourth position means the 30th day of the month. In this example, a Ford block date code of "5E30" represents May 30, 1995.