How To Tell if Your Truck Has a LM2 or LZ0 3.0l Duramax Engine

The LM2 3.0l Duramax Diesel engine in the GM 1500 platform was a smashing success for General Motors with great feedback from most of their customers. For the 2023 model year they released a revised engine where a number of items were changed to improve power, torque, reliability and efficiency. They are very similar from a quick glance but there are a few key differences that you can see to distinguish the difference. All GM 1500 trucks that are equipped with the Duramax Diesel in the model year 2023 are going to be equipped with the LZ0 engine option.

The most noticeable difference is the revised emissions components. You can see in the graphic below the Diesel Oxidation Catalyst, DOC, has been moved closer to the turbocharger for improved efficiency. This is a simple way to tell the difference, you can just pop the hood and look at the turbocharger.

lm2 or lz0 which Duramax engine does your truck have

The second way to tell the difference is by simply looking at the Vehicle Identification Number, VIN, the 8th digit in the VIN will tell you what engine option your truck is outfitted with. If the 8th digit is a "T" that means its and LM2, if the 8th digit is a "8" then you will know that your truck is outfitted with and LZ0.

It is helpful to understand your VIN for your own information, the first 3 digits are the World Manufacturer Identifier, otherwise known as the WMI and will identify where your vehicle was made. If the first digit is a 3, then it was made in Mexico, if it is a 1 then it was made in the US. The next 6 digits are the Vehicle Descriptor Section, VDS, it is used to specify the type of vehicle and may include information about the model, platform, engine and transmission. The final 8 digits are the Vehicle Identification Section or VIS.