The L81 3.0 liter V6 (VIN R) is standard. The eighth digit of the vehicle identification number provides engine identification according to the engine code letter. Engines contain two stampings (2) which are located on the rear of the cylinder block (1) near the transmission bellhousing mating surface and contain various engine production data.

The first stamping is a five position (6 digits) identification number which contains information on engine emission data (5), engine displacement (4), compression ratio (3), mixture system (2), and engine type (1).

The second stamping contains four positions (9 digits) and contains information on the engine catalyst type (4), engine type (3), the manufacturing plant (2), and the engine serial number (1).