- Max Speed: 55 mph
- Width: 80”
- Length: 222”
- Height: 79”
- Weight: 8,900 lbs
- Crew: 7 passengers + driver
- 6-13mm armor plating
- .50 cal M2 Browning machine gun
- .30 cal Browning M1919A4 machine gun
- Hercules JXD, 320 cu in (5,200 cc), L-head, inline 6-cylinder, gasoline
Design of the vehicle began at the White Motor Company, based in Cleveland, in 1937. It had .25 in (6.4 mm) face-hardened armor, full-time four-wheel drive, four-speed manual constant-mesh transmission, with one reverse gear, a two-speed transfer case, leaf spring suspension, manual steering, and (unusually for the period) vacuum-assisted power brakes.
The original order was for 64 units, all of which were given to the 7th Cavalry Brigade. Eventually the Army decided to adopt an improved version, designated M3A1. The new version had a longer and wider hull. In front of the bumper an unditching roller was mounted. The M3A1 could carry up to seven infantry and provide fire support with three machine guns – one .50 caliber (12.7 mm) and two .30 caliber (7.62 mm) – mounted on a skate rail around the hull.
Production of the M3A1 started in 1940 and lasted until 1944, with 20,918 vehicles built. The design influenced the later U.S. halftrack designs such as the M3 halftrack and the post-WW2 Soviet BTR-40. The early M2 halftrack copied the armor layout as well as the skate rail machine gun mounts.
The M3A1 first saw combat in the Philippines in 1941-1942, and was also used by the cavalry units of the US Army in the North African Campaign and the invasion of Sicily. It was used in traditional cavalry roles such as scouting and screening; also as an armored command vehicle. By mid-1943, the drawbacks of the design – its open top, poor off-road mobility, and poor armament – were evident. During 1943 most US Army units replaced the M3A1 with the M8 armored car and similar M20 Utility Car. A small number of M3A1s were retained and employed in Normandy. A few M3A1s were used by the US Marine Corps in the Pacific theater, but none saw combat.
The M3A1 was also supplied via lend-lease channels to the Soviet Union (3,034; these vehicles remained in service until at least 1947) and Britain, and used to equip Free French Forces, Belgian, Czechoslovak and Polish units.
This information, and more, available on Wikipedia’s Scout Car page.