Tractor, heavy, M1
Caterpillar tractor, crawler, diesel, model D7 from TB 5-9720-11, 1944
Type	Heavy tractor
Manufacturer	Caterpillar Tractor Co.
Length	194 in (4.93 m)
Width	98 in (2.49 m)
Height	108 in (2.74 m)
Weight	30,100 lb (13,653 kg)
Propulsion	Caterpillar tracks
Engine model	Caterpillar D7
Gross power	80 hp (60 kW)
Drawbar pull	21,350 lb (9,680 kg)
Speed	11 mph (18 km/h) Forward

M1 heavy tractor was a term used by the United States Army during World War II for several different models of "off the shelf" civilian tracked tractors adopted for military use. Under the Ordnance Department, these tractors were meant to tow artillery pieces, and were not equipped with blades like their Corps of Engineers counterparts. Later in the war, these tractors were replaced in the prime mover role by heavy trucks such as the Mack NO or purpose-built "high-speed tractors" such as the M4, M5, or M6. Some tractors were equipped with crane attachments for ammunition and material handling.

More than 1,000 were leased to the Soviet Union. They mostly used them to tow 122 mm, 152 mm, and even 203 mm guns. It saw good service as a prime mover for artillery.

• Allis-Chalmers Model L
• G-022 Caterpillar Model 60
• G-89 Caterpillar RD7,
• G-98, G-107 Allis-Chalmers HD-10DW
• G-101 International Harvester TD-18
• G-126 Caterpillar D7
• G-153 Caterpillar D8

and perhaps others.

• 
  Allis-Chalmers tractor, crawler, diesel, model HD-10W from TM 9-787A
• 
  International heavy tractor, crawler, diesel, model TD-18 from TM 9-1777A
• 
  International heavy tractor, crawler, diesel, model TD-18.second image from TM 9-1777A
• 
  Caterpillar tractor, crawler, diesel, model D7 from TB 5-9720-11, 1944
• 
  Caterpillar tractor, crawler, diesel, model D8 from TB 5-9720-11, 1944

• List of U.S. military vehicles by model number
• List of U.S. military vehicles by supply catalog designation
• M1 medium tractor
• M1 light tractor
• M2 light tractor
• Allis-Chalmers (See Military Machinery)

• TM 9-1777A Heavy tractor M1 International IHC TD-18
• TM 9-1777C
• TM 9-1773 Heavy tractor M1, Caterpillar D7
• TM 9-787A Heavy tractor M1, Allis-Chalmers HD-10W
• TM 9-1787A
• TM 9-1787B
• "TM-9-2800 1943 Standard Military Motor Vehicles".

• Drawings jexiste.be
• Use of M1 heavy tractor Caterpillar D7 through lend-lease in the Soviet Union
• Use of A-C HD-10W through lend-lease in the Soviet Union
• Use of IHC TD-18 through lend-lease in the Soviet Union

v t e US military soft-skinned vehicles of World War II
1⁄4–3⁄4 ton vehicles	Dodge WC series Dodge WC54 Ford Pygmy Willys MB / Ford GPW
11⁄2–4 ton trucks	Austin K2/Y Chevrolet G506 Diamond T 4-ton 6×6 truck Dodge T-234 "Burma truck" Dodge WC-62 and WC-63 Ford GTB 'Burma jeep' GMC CCKW Studebaker US6
5–10 ton trucks	6-ton 6×6 truck Autocar U7144-T & U8144-T K-30 truck K-31 truck Federal G-692 Kenworth M1 Wrecker M425 and 426 tractor trucks Mack EH series Mack LMSW Mack NJU Mack NM Mack NO
Tank transporters	M19 tank transporter M25 tank transporter 'Dragon Wagon'
Amphibious vehicles	Ford GPA "Seep" GMC DUKW "Duck" Landing Vehicle Tracked
Tracked tractors & carriers	M1 heavy tractor M1 light tractor M1 medium tractor M2 high-speed tractor M2 light tractor M4 high-speed tractor M5 13-ton high-speed tractor M6 high-speed tractor M7 snow tractor M29 Weasel
Motorcycles	Harley-Davidson WLA
Trailers	Ben Hur trailer Jeep trailer K-36 trailer K-38 trailer M5 bomb trailer
World War II vehicles of the United States List of soft-skinned vehicles of the US military