6.6L Duramax Engine Identification by VIN Number

Many model years were crossover or transitional years for the Duramax diesel, thus it is often necessary to decipher the engine model/version using the vehicle's VIN number. The chart below may be used to identify which Duramax engine your truck has based on the 8th digit of the vehicle identification number (VIN). Note that this is the vehicle identification number, not the engine serial number. The VIN number is located on the driver side door pillar, the driver side dash-mounted VIN plate, and the vehicle's title or registration card. It is important to identify which engine your have under the hood because not all components are identical nor interchangeable and may be specific to your engine version.