M6 Tractor

M6 High-Speed Tractor
Wartime photo of a M6 Tractor
Type	Artillery tractor
Place of origin	United States
Service history
Used by	US Army
Wars	World War II
Production history
Manufacturer	Allis-Chalmers
Produced	February 1944-August 1945
No.built	1,235
Specifications
Mass	76,000 lb (34.5 t)
Length	21 ft 6 in (6.55 m)
Width	10 ft 0 in (3.05 m)
Height	8 ft 8 in (2.64 m)
Crew	11
Main armament	.50 cal (12.7 mm)M2 machine gun
Engine	2 ×Waukesha145GZ 6-cylindergasoline engine 2 × 190 hp (140 kW) at 2,100rpm
Suspension	Horizontal Volute Spring Suspension
Operational range	110 mi (180 km)
Maximum speed	21 mph (34 km/h)

TheM6 High-Speed Tractorwas anartillery tractorused by theUS ArmyduringWorld War II.

Manufactured byAllis-Chalmers,it was used to tow heavy artillery pieces, such as the8-inch Gun M1and240 mm howitzer M1. ItsG-numberwas(G-184).

Development

Although in the late 1930s theUS Armylacked a clear mechanization policy, the success of the "blitzkrieg"in 1939-40 highlighted the need of motorized vehicles for both tactical and strategicmaneuver,which meant thattowed artillerywould need to move at a speed comparable to that of thearmored fighting vehicles.

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

Intended to tow heavy artillery pieces as the240 mm howitzer M1and the8-inch Gun M1,the M6 artillery tractor was larger and heavier than theM4 Artillery Tractor,although they had a similar layout. The main differences between both were in the following areas:

• Running Gear (6 running wheels in the M6, instead of 4 wheels in the M4)
• Dimensions
• Weight
• Towing capacity
• Engine

It was powered by two six-cylinder, in-line, Waukesha 145GZgasolineengines with anengine displacementof 13.4 L (820 cu in), each of which gave 190 hp (140 kW) at 2,100 rev/min. 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 theM3 Light Tankand later in the M4 Tractor.

Service history

The M6 tractor was chiefly used in theEuropean theateronly in the last months of World War II. Until then large caliber artillery was moved by theM1 Heavy Tractor,heavy trucks, or vehicles such as theM33 Prime Mover,M34 Prime MoverorM35 Prime Moverderived from theM3 Medium Tank,M4 Medium Tank,andM10 GMChulls respectively

Use of this tractor in thePacific theaterseems to have been limited to training atOahu,(Hawaii).

Some vehicles were sold toIsraelafter being replaced byself-propelled artillery.

Users

• US Army

Surviving vehicles

• Overloon War Museum,Netherlands

National Military Vehicle Museum, Edinburgh, South Australia

Gallery

• 
  M6 tractor, Overloon
• 
  Side view, M6 tractor, Overloon
• 
  Front view, M6 Tractor, Overloon
• 
  Rear view, towing an 8-inch howitzer M1, Overloon

See also

• List of U.S. military vehicles by model number
• List of U.S. military vehicles by supply catalog designation(G184)

Comparable vehicles

• M4 Tractor
• M5 Tractor

References

Bibliography

• Crismon, Fred W. (1992).US military tracked vehicles.Osceola: Motorbooks International.ISBN0-87938-672-X.
• Doyle, David; Pat Stansell (2006).High speed tractor.Delray Beach: Ampersand Publishing.ISBN0-9773781-0-1.

Further reading

Technical manuals

• SNL G184
• TM 9-2800 1943 Military vehicles
• TM 9-2800 1947
• TM 9-2800-1 1953
• TM 9-788
• TM 9-1785A
• TM 9-1788
• TM 9-1825A
• TM 9-1826C
• TM 9-1827A
• TM 9-1828A
• TM 9-1829A

Books and publications

• Trewhitt, Phillip (1999).Armoured Fighting Vehicles.Expert Guide. Bristol: Dempsey Parr.ISBN1-84084-328-4.

External links

• Olive-Drab website, Highspeed M4(accessed 2014-03-02)

Media related toM6 High Speed Tractorat Wikimedia Commons