M1 Heavy Tractor

Prior to and during the second world war the US Army called several tractors M1 Heavy Tractor. Under the Ordnance Corps these "off the shelf" tractors were meant to tow artillery pieces so were not equipped with blades like their Engineer counterparts. Eventually these were replaced by purpose built "High Speed Tractors" (HST). Some tractors were equipped with crane attachments for ammunition, and material handling.

More than 1000 were leased to the Soviet Union. They mostly used them to tow 152 mm guns, 122 mm guns, even 203 mm guns. It saw good service as a prime mover for artillery.

Variants
and perhaps others
 * 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