The 18-ton M4 higher level tractor series is developed and built by the Allis-Chalmers production company of Milwaukee , Wisconsin , between 1943 and 1945. The look ended up being on the basis of the T9 and T9E1 was indeed standardised since the moderate Tractor M4 which became the tall Speed Tractor M4.Together using the M5 and M6 tall Speed Tractors they replaced the older commercial-type crawler tractors which mightn't meet with the needs of a contemporary mechanized military any more. The high rate tractors could carry both crew and an easy option of ammo. Production were limited to purchase in March 1943 and 5552 M4 tractors were assembled until June 1945,plus 259 M 4A 1 tractors between June and August 1945. The 18-ton M4 higher level tractor finished up being developed primarily as a prime mover the 155mm weapon? and 8-inch and 240mm howitzers.
