Converting older vehicles with Cummins 3.9L 4BT and 5.9L 6BT diesels has been popular for decades, because the engines are well-known for their simplicity, efficiency, availability, and reliability.

Cummins ReCon Parts and Engines are not just simply repaired or rebuilt, but remanufactured to be identical to brand new Cummins Genuine Parts, adhering to the original specifications.

Cummins also made a 3.9L four-cylinder version of the 12-valve called the 4BT. This engine has the advantage of being much shorter, and about 300 pounds lighter than it's bigger brother.