The U.S. armed forces used Caterpillar crawler tractors to clear ground, build roads and airfields, and tow guns and heavy loads. From 1942 to 1945 Caterpillar delivered about 51,000 of them to the military.
The five diesel models, D2 to D8, stand here side by side to scale. Choose one to see how it changed, series by series, from the 1930s to the first post-war version.