M6 Tractor


The M6 High-Speed Tractor was an artillery tractor manufactured by Allis-Chalmers and used by the US Army during World War II to tow heavy artillery pieces, such as the 8-inch Gun M1 and 240 mm howitzer M1. Its G-number was .

History

Background

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.
To achieve this, a series of “high speed tractors” was planned, which would tow the different artillery pieces existing in the US Army inventory. The “high” speed was considered in comparison with horse-drawn artillery rather than that obtainable with wheeled prime movers or ballast tractors. The models considered in the series included: 7 ton, 13 ton, 18 ton, and 38 ton.

Development

Description

Intended to tow heavy artillery pieces as the 240 mm howitzer M1 and the 8-inch Gun M1, the M6 artillery tractor was larger and heavier than the M4 Artillery Tractor, although they had a similar layout. The main differences between both were in the following areas:
It was powered by two six-cylinder, in-line, Waukesha 145GZ gasoline engines, each of which gave 190 HP at 2,100 rev/min, with an engine displacement of 13,400 cm³.
The running gear consisted on six rubber-rimmed wheels per side, with the drive wheel located at the front and a large tensioning wheel at the rear; a layout similar to the one used in the M3 light tank and later in the M4 Tractor.

Variants

Combat use

European front

The M6 tractor was used in the European theater only in the last months of World War II.
In the meanwhile, the movement of large caliber artillery was done by the M1 Heavy Tractor, heavy trucks, or vehicles based on existing hulls, among them:
Use of this tractor in the Pacific theater seems to have been limited to training at Oahu,.

Post-war

In the Korean War no heavy artillery was used that required being towed by these tractors.
Some vehicles were sold to Israel after being replaced by self-propelled artillery.

Users