For more than half of the 20th Century, the 2-1/2-ton 6x6 truck was the backbone of US military tactical transport. The pace-setter for this type of vehicle was the GMC CCKW, which not only served as a transport, but also formed the basis for a myriad of specialized vehicles: air-transportable versions multiple engineering variants, mobile medical facilities, anti-aircraft weapons, and trucks that fulfilled a host of other tasks. The CCKW has been the subject of a number of books and articles over the years, but this volume is the first to draw on the archival records of General Motors to trace the truck to its roots in the 1939 ACKWX and then tell its story through its debut in 1941 and the varied services it rendered with US forces in all theaters in the ensuing decades. GMC's obvious role is covered, but so too are less-known stories, such as the contribution made by multiple Chevrolet facilities to CCKW production. The book describes the development, production, and US use of the CCKW, ACKW, AFKWX, and CCW in WWII and Korea.