Bumper date codes

[aboss4tg]

I have two original front bumpers with date codes, 8 15 M4, and 1 31 M3
How do you decipher the date codes?

Todd

[FL SAAC]

I have two original front bumpers with date codes, 8 15 M4, and 1 31 M3
How do you decipher the date codes?

Todd

According to Mike our resident expert:

The Ford bumper date code "8 15 M4" indicates the part was manufactured on August 15 (month 8, day 15). The "M4" likely represents the stamping plant code and potentially the model year or shift.


8: The month of manufacture, which is August.

15: The day of the month, the 15th.

M: This is likely the code for the specific Ford stamping plant where the bumper was made.

 For instance, in some classic Ford documentation, 'M' could stand for a specific plant or be part of a plant/year code combination.

4: This digit typically indicates the model year the part was intended for or the last digit of the actual calendar year of production.

For example, this could be for a 1974, 1984, 1994, etc., model year vehicle. The exact decade can usually be determined by looking at the car's overall production era or other date codes/part numbers on the vehicle.

Ford used several date code formats over the years, but the basic format of month-day-plant/year is common for stamped parts like bumpers and sheet metal.

[J_Speegle]

What year or years are the bumpers?  Can make a difference in the dating pattern and can make decoding easier.

[aboss4tg]

Both are for the 65-66 Mustang.

[J_Speegle]

Both are for the 65-66 Mustangs

Looking at data collected from unrestored cars I currently believe you will find the dating pattern as following

Month- day of month - stamping plant (Monroe) - the year Like most sheet metal stamping patterns the decade is not include in the pattern/coding. Other than that there were changes though the decades to the finished product as the stamping molds wore and possibly repaired or replaced due to issues.

Hope this helps

[aboss4tg]

This helps as my 66 Hertz was produced in early Feb. and did not have the original bumper, so I plan on re chroming the 1-31 M3 which should be coded correctly for my car. TY

[J_Speegle]

This helps as my 66 Hertz was produced in early Feb. and did not have the original bumper, so I plan on re chroming the 1-31 M3 which should be coded correctly for my car. TY

Well IMO at least the month and day of month would be an "acceptable". Possible originally stamped in 1973 or 1983 even

If nothing else it would be a good place keeper if you wanted to continue to search for a "better" one.  Nice things about bolt-on parts 


Here's a half dozen examples from unrestored 65 and 66 Mustangs (same as Shelby) showing the location and stamping pattern - have more of course