The Willys MB Jeep: Three Makers, One Wartime Design

The Willys MB, the best-known wartime Jeep, was not the work of one company. It came out of a 1940 US Army request that three firms answered, and the final design mixed parts from all of them. About 639,000 Jeeps were built for the Allied forces in the Second World War, including the near-identical Ford GPW. This article follows how the design took shape, using the Studebaker National Museum and the National Motor Museum in the United Kingdom.

The Army's 1940 request

According to the Studebaker National Museum, the Army wanted a small, light, general-purpose vehicle with four-wheel drive that could carry a light machine gun. In 1940 the first two suppliers were American Bantam, with its BRC model, and Willys-Overland, with its Quad, a four-by-four. Fewer than 100 vehicles were built that year.

The National Motor Museum says Bantam built a prototype four-wheel-drive runabout to meet the specification, and that the firm built 1,500 production vehicles but lacked the capacity for military demand. Assembly was therefore split between Willys-Overland and Ford.

Three versions in 1941

After early trials the Army asked for changes and opened development to other makers, notably Ford. The Studebaker museum reports that almost 8,500 vehicles were built in 1941 in three versions: the Bantam BRC-40, the Willys MA and the Ford GP. Each firm was now producing its own take on the same brief.

How the MB took shape

Late in 1941 the design was standardised. The Studebaker museum says it used a Spicer differential, the Willys Go-Devil engine and Ford's body configuration, and describes the result as Bantam's Spicer-sourced drivetrain combined with the Go-Devil engine and Ford GP bodywork. Willys built this standard model as the MB, and Ford built it as the GPW.

Sources differ in how they spread the credit. The National Motor Museum names Bantam as the builder of the original prototype, while the Studebaker museum stresses the shared nature of the final design. Both agree the MB and GPW used the Willys Go-Devil engine.

• Bantam: the early prototype and the drivetrain parts used in the standard design.
• Willys-Overland: the Go-Devil engine, and the MB version.
• Ford: the body configuration, and the GPW version.

The engine and the specifications

The National Motor Museum describes its 1943 Willys MB as having a 2,199 cc, in-line four-cylinder, side-valve engine, four-wheel drive and a top speed of 60 miles per hour. It notes that the car was not marketed to the public until 1945.

Production numbers

The Studebaker museum gives 639,235 Jeeps built during the war and says Willys made over 360,000 of them. It also reports almost 13,000 amphibious Ford GPA Jeeps, nicknamed the "Seep", and a total of 647,925 Jeeps from 1940 to 1945. The National Motor Museum gives 639,245 military Jeeps between 1941 and 1945. These counts are close but not identical, and the museum figures do not fully reconcile with each other, so it is safest to say about 640,000.

Service in the war

The National Motor Museum says the Jeep served with Allied forces in virtually every theatre of the Second World War. The example in its collection took part in the Normandy landings of June 1944.

After the war

Civilian production continued after 1945. The National Motor Museum calls the Jeep the ancestor of the modern off-road four-wheel-drive vehicle and the sport utility vehicle (SUV). That claim is a museum's summary rather than a precise count of descendants, but it shows how far the Army's small reconnaissance vehicle reached beyond the battlefield.

The story is also a reminder that wartime products often came from shared work. The Army set the requirements, three firms competed and borrowed ideas, and two of them built the final model side by side.

Sources

• The Jeep in World War II, Studebaker National Museum
• Willys MB Jeep, National Motor Museum