The M8 Greyhound was he standard armored car used by the US Army during World War II and with a service life that has lasted until today with the numerous foreign users which it was exported to. The M8 was a 6 x 6 design with an all-welded hull. The driver compartment was located at the front and the engine at the rear, while the center featured a rounded open hull mounting a 37-mm M6 gun. This was insufficient against enemy armor but nevertheless offered some degree of firepower if needed, especially against enemy recon units. Armor protection was rather thin, and it was particularly vulnerable to mines which required some ad hoc defensive measures such as fitting the floor of the hull with sandbags. The M8 (and its scout car variant, the M20) saw extensive use during World War II where its cross-country mobility gave it good performance in most terrain, and was also supplied to numerous Lend-Lease partners although the British were not drawn by its weak armor. It remained in US service during the Korean War where it also was used but retired thereafter. In the post-war period it was supplied to many countries where it was used in numerous wars, notably by the French in Indochina. They remain in service in many Latin American countries today for both military and policing duties.

Numerous prototypes for what became the M8 were developed in 1942, these included the Ford T22 (6 x 6) and T22E1 (4 x 4), while the Fargo Company produced the T23 (6 x 6) and T23E1 (4 x 4). Ultimately the T22 was selected in a redesigned form known as the T22E2 which was later standardized as the M8 Light Armored Car. The need for a command vehicle and a cargo carrier resulted in the T20 and T26 prototypes, which were later combined into the M20. This had the turret removed in favor of a ring mount for a .50-in (12.7-mm) machine gun and was used as a scout car as well as a personnel and cargo carrier. A planned post-war successor known as the M38 was never produced.