Diamond T 509 (1939 to 1948)

The Model 509 was introduced in 1939 by Diamond T as a heavy military truck for the United States Army during World War II. Designed as a 4 ton 6x6, it featured all wheel drive on all three axles, allowing it to operate effectively in difficult terrain. It was equipped with a 8.7L Hercules RXC inline 6 engine, paired to a 5 speed manual transmission with a 2 speed transfer case. It was offered primarily in cargo, tractor and special variant configurations, all with a conventional 2 door enclosed cab. After the war many examples were sold as military surplus and subsequently used as commercial vehicles in the 1940s and 1950s, particularly in construction, logging and rural heavy transport, due to their robustness and payload capacity. The Diamond T 509 was produced until 1948.