If you are custom building your own heavy-duty truck, picking the engine is obviously one of the most important steps in the process. A lot of custom builders will go with a diesel engine, and it is for good reason. Diesel engines have the ability to yield much more torque, much more hauling capacity, and much more life. The 6.0L diesel engine is a highly sought after model. If you are looking for the best for your truck, you are bound to have a few questions.