The Cummins engine known as the "Million-Mile Diesel" was the 5.9-liter inline six-cylinder 12-valve turbodiesel engine that was an option on the Dodge Ram 2500 and 3500 trucks produced between 1989 and 1998. Instead of depending on electronic complexity, it operates mechanically, which can get some owners into the Cummins million mile club. In addition, this older Cummins engine does not have any of the emission-reducing technologies that current electronically-controlled diesel engines must be equipped with. The Cummins Million-Mile Diesel is also very impressive for its mechanical failure rate of less than one percent. This compares very favorably to the failure rate of the early electronically-controlled engines, which was over 15 percent.