TM 9-803 Willys-Overland MB and Ford Model GPW Jeep Technical Manual Army U. S.Paperback

Designated as a light truck, the Jeep was the primary four-wheel drive vehicle for the U.S. The Jeep's design owed a great deal to Karl Probst, a freelance designer employed by the American Bantam Car Co. Army during WWII.

It clearly impressed the Army in head-to-head competition against a design submitted by Willys-Overland. Probst's prototype "Blitz Buggy" was built in a mere 49 days. However the Buggy's engine failed to meet requirements, and the Army determined that Bantam could not produce the vehicle in quantity.

As a result, the Army bought the Bantam design and asked both Willys and Ford to improve it. The Willys model MB, equipped with a L134 straight-4 "Go Devil"engine, was eventually accepted as the standard. Ford models built to Willys specifications were designated GPW ("G" for government vehicle, "P" designating the 80" wheelbase, and "W" indicating the Willys engine