Manufactured by Allis-Chalmers, it was used to tow heavy artillery pieces, such as the 8-inch Gun M1 and 240 mm howitzer M1.

Although in the late 1930s the US Army lacked a clear mechanization policy, the success of the "blitzkrieg" in 1939-40 highlighted the need of motorized vehicles for both tactical and strategic maneuver, which meant that towed artillery would need to move at a speed comparable to that of the armored fighting vehicles.

The "high" speed was considered in comparison with horse-drawn artillery rather than that obtainable with wheeled prime movers or ballast tractors.

The M6 tractor was chiefly used in the European theater only in the last months of World War II.

[citation needed] National Military Vehicle Museum, Edinburgh, South Australia Media related to M6 High Speed Tractor at Wikimedia Commons