In 1939-1941 the Army Ordnance Corps was developing a complete line of tactical trucks that could operate over all roads and cross-country terrain in all weather.

This 501 cu in (8.2 L) overhead valve inline 6 cylinder gasoline engine developed 145 hp (108 kW) at 2400 rpm and 372 lbf⋅ft (504 N⋅m) of torque.

[7] In addition to the wrecking body, all trucks had a 20,000 lb (9,100 kg) front winch and a rear pintle hitch.

[8] The -A1 upgrade also had a rear winch, heavier bumpers, and a large front tow-bar, allowing the truck to recover and move light armored vehicles.

Outriggers and braces on both the body and the boom itself allowed 16,000 lb (7,300 kg) to be lifted throughout the rear 180° of the truck.