Military Police units have the mission, among many others, to provide armed escort to supply convoys in a combat zone. During the Vietnam War there were never enough military police combat support units to accomplish this mission. Commanders of truck companies in the 8th Transportation Group began to arm and armor 2-1/2 ton and 5 ton cargo trucks to provide convoy security. The 8th Trans Group became the major user of gun trucks during the war.
This book, number 184 in the New Vanguard series published by Osprey Publishing, describes the development and employment of gun trucks during the last half of the Vietnam War. The first half of the volume describes the U.S. Army motor transport units deployed in South Vietnam, the Army convoy system itself, and the threat the convoys faced. The second half provides a good description of gun truck design and development and gun truck tactics.