Because of combat operations in Iraq, the U.S. Army is sending ten times as many heavy trucks back to the factory for rebuilding. Before the Iraq war, about 25 heavy trucks a month would go back for refurb. Now its up to 250 a month. Before, it was accidents, or heavy use, that got trucks sent back. Now its combat damage. This includes lots of bullet holes and damage from roadside bombs. The backbone of the U.S. Armys truck transport force are its 13,000 Heavy Expanded Mobility Tactical Truck (HEMTT). These eight wheeled vehicles come in five different configurations, the most common being the cargo carrier (ten tons carried in the truck, plus another ten tons in a trailer) and tanker (2500 gallons). The vehicle weighs 19 tons, has a max speed of 90 kilometers an hour and a range (on one tank of fuel) of 480 kilometers (less if moving cross country.) There are also 2,000 HET (Heavy Equipment Transporters). These are 42 ton semi-trailers that can carry up to 70 tons. Their main job is hauling M-1 tanks long distances. But HETs can also carry supplies, and often do. HETs are also shot at in Iraq, but fewer of them are used for supply runs.