 During World War II the most important model for the U.S. Army was the GMC CCKW or 'Jimmy', with over 560,000 units built.Another 200,000+ deuces were Studebaker and REO US6, built primarily for Lend-Lease export, mostly to the Soviet Union, and many others have been exported to smaller militaries.In addition to the 6x6 trucks, a significant minority of these trucks were also built minus the front-wheel drive, as 6x4 trucks.