In 1917 after some successful years using the Holt civilian tracked tractors as an artillery towing vehicle, it was determined the U.S. Army needed a specialized towing vehicle. It was concluded that civilian tracked vehicles lacked armored protection for the engine and fuel system, flexible towing speeds and maximum speeds, and the track system needed to be enhanced for road towing. The US Army decided to categorize their artillery tractors on the maximum drawbar pull. The 5-ton was designed to improve the noted deficiencies.
The 5-ton was originally selected as the tow vehicle for the trailers of the British designed 9.2-inch Siege Howitzer. It was agreed that the 9.2-inch would be suitable as the Army’s primary heavy gun. Since the 9.2-inch howitzer was a massive piece of equipment it was detached into 3 pieces for transport. Each load was to be pulled by a single 5-ton tractor. After entry into the First World War in early 1917, the U.S. Army recognized the vital need for tracked artillery tractors and ordered 11,150 5-ton tractors. This was the largest order of all other track vehicles combined.
The five-ton tractor entered production in July of 1918. By the time the Armistice was signed on November 11th, 1918, over 1,540 5-ton vehicles had been accepted in service, with another 459 shipped to France. By January 31st, 1919, the number of 5-ton tractors accepted had grown to roughly 3,480. The primary designer and supplier of the 5-ton tractor was the Holt Manufacturing Company. With production exceeding Holt’s capacities, five other firms also produced the five-ton tractor, Chandler’s Motor Car Company, REO Motor Car Company, Maxwell Motor Car Company, Federal Motor Truck Company, and Interstate Motor Company. After the war some of the 5-ton tractors remained in service through the 1920s. This one was built by REO Motor Car Company
