GM Service Manual Online
For 1990-2009 cars only

Engine ID and VIN Derivative Location

The Vehicle Identification Number (VIN) Derivative is located on the left side rear of the engine block (1) or on the right side rear (2) and typically is a nine digit number stamped or laser etched onto the engine at the vehicle assembly plant.

    • The first digit identifies the division.
    • The second digit identifies the model year.
    • The third digit identifies the assembly plant.
    • The fourth through ninth digits are the last 6 digits of the Vehicle Identification Number (VIN).

Object Number: 1247568  Size: MF
(1)Engine ID Location
(2)Engine ID Location
(3)The first digit identifies the engine build location - All first digits will be a T, this engine is only being built at Tonawanda
(4)The second and third digit identifies the build year
(5)The fourth, fifth and sixth digits identify the build month - Julian Date
(6)The seventh through tenth digits identify the engine build sequence

Object Number: 1257809  Size: MF
(1)Engine ID Location
(2)Engine ID Location
(3)The first digit identifies the engine build location - All first digits will be a T, this engine is only being built at Tonawanda
(4)The second and third digits identifies the build year
(5)The fourth, fifth and sixth digits identify the build month - Julian Date
(6)The seventh through tenth digits identify the engine build sequence