Diamond T tank transporter The Diamond T Tank Transporter was a heavy tank transporter , used in World War II and the following years . Designed as a heavy prime mover for tank transporting , the Diamond T 980 was the product of the Diamond T Company in Chicago . In 1940 the British Purchasing Commission , looking to equip the British Army with a vehicle capable of transporting larger and heavier tanks , approached a number of American truck manufacturers to assess their models . The Diamond T Company had a long history of building rugged , military vehicles for the U . S . Army Quartermaster Corps and had recently produced a prototype heavy vehicle for the US Army which , with a few slight modifications met British requirements and an initial order for 200 was very quickly filled . The result was the Diamond T 980 , a 12 - ton hard - cab 6x4 vehicle which proved to be one of the most successful and memorable in its class . Powered by an Hercules DXFE OHV inline six diesel engine developing , or the Hall - Scott 440 OHV inline - six gasoline engine ( the largest gasoline engine in any WW2 military truck ) of , and geared very low , it could pull a trailer load of up to , and proved capable of the task of moving the heaviest tanks then in service . It had a four - speed manual constant - mesh transmission plus a similar three - speed auxiliary gearbox , for a total of twelve forward and three reverse speeds , and airbrake s . The electrics were 24 - volt . Top speed was , and with fuel , maximum range was . Wheelbase was , length , track , and height . Steering was manual , with no power assist . A winch of capacity , chain drive n off the auxiliary transmission and intended mainly for hauling damaged tanks aboard trailers , was mounted behind the cab . The 981 was the same chassis with open and / or closed cab and cargo box the winch could be used through the front and rear and was 200 ' longer . Both the 980 and 981 used a cab design similar to the 4 - ton truck . Service . Production began in 1941 . The first batch of the vehicles was received in Britain in 1942 and very quickly demonstrated their rugged reliability in the British campaign in North Africa . Battle - damaged tanks needed to be quickly recovered , often under hostile fire , and returned to workshops for repair . The Diamond T , with its well trained Royal Army Service Corps crew and powerful engine and winch , could accomplish this , even in the harshest desert conditions . Some 6 , 000 were eventually built by 1945 and were used by virtually every Allied army in every theatre of WWII . The British Army took delivery of around 1 , 000 during the war years and many continued in service afterwards , being replaced in the early 1950s with the Thornycroft Antar ( " Mighty Antar " ) although a few " T ' s " remained in tank transporter units up to 1971 . Many of those sold off by the Army after the war were snapped up by heavy haulage and recovery specialists , notably Pickfords and Wynns , and they were a familiar sight on Britain ' s roads , pulling heavy lowloaders and fairground trailers or parked on garage forecourts , in readiness for a heavy rescue operation equipped as Wreckers ( breakdown recovery trucks ) . It suffered from " very limited off - road performance " as a result of only the two rear axles being driven . Today many of the 70 year - old Diamond T ' s can still be found in private ownership in Britain and frequently appear at historic vehicle shows . U . S . nomenclature . This combination unit is referred to as the M19 tank transporter , consisting of the M20 tractor and M9 24 - wheel trailer . In the nomenclature system used by the U . S Army Ordnance Corps Supply Catalog this vehicle is referred as the G159 . It was superseded by the M26 , which would use the same Hall Scott 440 engine . After the introduction of the M26 , the U . S . relegated M20s to ammunition hauling , for which they proved " tremendous " .