By the mid-1980s, these vehicles were replaced with the ÖAF 32.281 FDA “PK 30” recovery vehicles.The first prototype of the Diamond M20 with M9 low-loader trailer was developed for the US army in 1940 as tank transport system M19. In 1941 200 such systems were delivered to the British Military, some of which ended up with the British 8th Army in North Africa.
The Diamond M20 Mod 980 tractor is equipped with a Hercules DFXE inline 6-cylinder diesel engine with a (for its time) respectable power output of 185 HP from its 14.7 liter volume. In order to provide the necessary towing capacity for the 50-ton tank-trailers, its transmission was extremely short, resulting in a top speed of less than 40 km/hr. This system was capable of transporting even the heaviest contemporary allied tanks, still it was rapidly replaced by the even heavier system M25, consisting of the M26 tractor (“Pacific”) with the M15 trailer.
Between 1941 and 1945 5871 Diamond M20 were produced, some of them also ending up with the Soviet armed forces as part of the Lend-Lease program.
The Austrian Army kept the M19 and M25 systems in service until the mid-1960s when the new Austrian Gräf & Stift ZAFD 230 heavy tractors were introduced.
