The GMC CCKW U.S. Army cargo truck, the original “Deuce and a Half”, was the working horse that kept Allied armies supplied after the Normandy invasion. The designation CCKW comes from standard GMC terminology: C for a 1941 model year; C for a conventional cab configuration; K for selective front-wheel drive; and W for two powered rear axles. It’s development began in 1939 and the US Army specified this size because it has the truck fit on Navy ships and was also suited for mass production.
With so many CCKW been built by the end of the war, the truck remained in service in the US Army and its European allies for decades after its peak had passed. Its legacy can still be seen, however, in every Chevrolet/GMC truck built since the war.