Specifications of M939 6x6 diesel trucks include a 14-liter naturally-aspirated inline 6-cylinder diesel engine pushing 240 horsepower and 685 pound-feet of torque, an Allison 5-speed automatic transmission and a low range front axle. Further, the M939 truck features R20 tires and has a weight of 22,750 pounds.
Developed in the 1970s, M939 6x6 diesel trucks are a series of military trucks that are an updated version of the M809 series. The M939 is typically used for transporting a wide range of supplies, and it is especially used for traveling on hard-surfaced roads. Today, a large number of M939s are still in use by the military, although they are being replaced slowly by the new MTVR series of truck.
Every truck in the M939 line shares the same chassis, cab, hood and fenders. The basic M939 truck has three axles and six powered wheels, making it 6x6. M939 models also make use of a Cummins NHC 250, however a M939A2 variant utilizes a Cummins 6CTA8.3.
The M939 sports 11:00 R20 tires that have two tires per axle per side, making them rear tandem duals. The M939 series has three different wheelbases: a short one made for tractors and dumps, a long one used for cargo, and an extra long one made for longer cargo and vans.