GM Service Manual Online
For 1990-2009 cars only

Object Number: 174107  Size: SH
    • 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 six digits of the Vehicle Identification Number (VIN).

Object Number: 195338  Size: SH
    • Engines built at the Tonawanda engine plant have the engine identification number located at the right front top of the engine block.
       - The first digit (1) is the source code.
       - The second and third digits (2) are the month of build.
       - The fourth and fifth digits (3) are the date of build.
       - The sixth, seventh, and eighth digits (4) are the broadcast code.

Object Number: 195339  Size: SH
    • Engines built at the Romulus engine plant have the engine identification number located at the right front top of the engine block.
       - The first digit (1) is the source code.
       - The second and third digits (2) are the month of build.
       - The fourth digit (3) is the hour of the build.
       - The fifth and sixth digits (4) are the date of build.
       - The seventh, eighth, and ninth digits (5) are the broadcast code.