You have probably seen the video of the Melroe M870 Buffalo Coal Dozer on the webs. It is powered by 2 NTC 855 Cummins Diesel Motors. The front motor is weaker and tends to smoke. Each have 335HP. It also has 2 Clark torque converters and a Clark 4 speed power shift transmissions. Each drive train runs on along it's side of the dozer. One side has Rockwell hubs while the other side has Caterpillar hubs. The massive 23 foot blade has plates welded o it to assist in the moving big piles of coal. It rolls the 20,000 pounds on 65/35-33 42 ply tires.