World War II jeep design was the culmination of a long period, including contributions from U.S. military officers as well as civilian engineers. The concept of the jeep came from the infantry, who required a small, powerful four-wheel drive vehicle — the latter was mainly related to three companies: Bantam, Willys and Ford, and the production has been repeatedly called a "committee design." In autumn 1941, U.S. Lt. E.P. Hogan Quartermaster Corps wrote: "No one person or manufacturer may take credit for the original 1⁄4-ton truck design of the Army. This vehicle is the culmination of a lot of work and many tests."Hogan credited both military and civilian engineers, particularly those working at the Quartermaster Depot of Holabird.
Advances in early 20th-century technology resulted in widespread military mechanization during the First World War. In that war , the United States Army deployed thousands of motor vehicles, including some 12,800 Dodges, and thousands of four-wheel drive trucks: Jeffery / Nash Quads, and Four Wheel Drive Auto Company (FWD) trucks. General John Pershing considered horses and mules acceptable for the preceding three U.S. wars, but his cavalry forces had to move faster in the new century, with more range and more personnel.
Immediately after the First World War, the use of motor vehicles in that war was only considered a prelude to much greater use in future armed conflicts. As early as 1919, the U.S. Quartermaster Corps recommended the acquisition of a new type of military vehicle, "...of light weight and compact size, low silhouette and high ground clearance, and capable of carrying weapons and men across all sorts of rough terrain." The U.S. Army began to search for a small vehicle suitable for recognition and messaging while simultaneously searching.There was a push towards standardisation at the same time. At the end of World War I, U.S. troops overseas had a total of 216 motor vehicle makes and models to operate, both domestic and international, with no sufficient supply chain to keep them going.
Various light motor vehicles were tested — with and without sidecars at first motorcycles, and some adapted Ford Model Ts. In the early 1930s, the U.S. In a 1933 article in Popular Mechanics magazine, an army experimented with a bantam weight "midget vehicle" for scouts and raiders-a 1,050-pound low-slung car with a lightweight pick-up body was seen. When the United States became after 1935 Congress made vehicles of the First World War obsolete, and further attention was gained from acquisition for "remotorizing the Army." In 1937, Marmon-Herrington launched five 4 range Fords, and in 1938, American Bantam produced three Austin roadsters.Elsewhere, Japan had already conquered Manchuria in 1931 in Asia and the Pacific, and had been at war with China since 1937. The Imperial Army used the Kurogane Type 95, introduced in 1936, a compact three-man crew, four-wheel drive car for reconnaissance, and troop movements.
By 1939 the army started standardizing its general-purpose truck chassis types by payload rating, initially in five classes from 1⁄2 tons to 7 1⁄2 tons, but the categories were revised in 1940. In the first time, at the bottom of the scale, a quarter-ton truck chassis class was added and a 3⁄4-ton chassis supplanted the 1⁄2-ton group.The U.S. Department of War had decided by the eve of World War II that it wanted a 1⁄4-ton, cross-country observation vehicle. While 1⁄2-ton four-by-four trucks had outperformed 1 1⁄2-ton 4x4 trucks during testing in 1938, the half-ton 4x4 trucks – both from Marmon-Herrington Ford and the 1940 Dodge VC series – still proved to be too big, too heavy and too agile off-road. Anxious to get a four-ton truck in time for America's entrance into the Second World War, the U.S. The army asked domestic automobile manufacturers for proposals.Recognizing the need to develop uniform standards, on July 11, 1940, the Army formalized the criteria and sent them to 135 U.S. automakers.
The War Department aimed to standardize by July 1941, and agreed to pick a single company to supply them with the next order for 16,000 vehicles. Willys won the contract primarily because of his much more powerful 60 HP engine (the "Go Devil"), which the soldiers were raving about, and its lower cost and appearance. The design features were then introduced into the Willys car in the Bantam and Ford entries that reflected an improvement over Willys' design, changing it from a "A" category to "B," hence the nomenclature "MB." Most noticeable was a broad flat hood, modified from Ford GP.The jeep had implemented many new automotive innovations once it reached mass production. For the first time having four-wheel drive introduced the need for a transfer case, and the use of constant velocity joints on the driven front wheels and axle, to a regular vehicle sized in the production car.
By October 1941, it became clear that Willys-Overland was unable to keep up with the demand for production, and Ford was also contracted to build jeeps using Willys designs, drawings , specifications, and patents, including the Willys engine. The Ford car was later called "GPW," with the "W" referring to the design and engine approved for the "Willys." Willys produced 363,000 Jeeps and some 280,000 Ford during World War II. Under the Lend-Lease program about 51,000 were exported to the U.S.S.R.
Ford faithfully assembled jeeps with virtually compatible parts and materials, partly encouraged by the use of materials from common sources: Midland Steel frames, Kelsey-Hayes wheels, and Spicer axles and transfer cases. There were, however, many slight differences; the most well-known: the Ford chassis had an inverted U-shaped front cross member instead of a tubular frame, and many small parts were stamped with a Ford script letter "F" Many body detail differences remained until January 1944, when both Ford and Willys adopted a composite body, manufactured by American Central. It embedded features of both designs.Due to the chaotic circumstances of the war, sometimes peculiar deviations from regular mass production came off the assembly line, which collectors now appreciate — for example: the earliest Ford GPWs had a Willys design frame, and in late 1943 some GPWs came with an unmodified Willys body; and in 1945 Willys produced some MBs with a deep mud exhaust system, vacuum windshield wipers, and Jeee's windshield wipers.
In 1943 Willys-Overland filed a patent for the name "Jeep." In 1945 onwards, with its CJ (Civilian Jeep) models, Willys sold his four-wheel drive vehicle to the public , making these the world's first mass-produced 4WD civilian cars. Even before real civilian purpose jeeps were made, a story titled 'US Civilians Buy Their First Jeeps' was published in the January 3, 1944 issue of Life magazine. In 1943, a mayor from Kansas had purchased a Ford GP in Chicago, and he did useful work on his 2,000-acre farm.
Industrial designer Brooks Stevens had already come up with an idea in 1942 about how to build a civilian car called Victory Car on the Jeep chassis. It never went into production but Willys liked the concept and more assignments were given to Brook Stevens including the Willys Jeep Station Wagon in 1946.
The U.S. In 1948 The Federal Trade Commission agreed with American Bantam that the American Bantam had created and developed the concept of making the Jeep in cooperation with the United States. Military, Ford and Spicer too. The commission forbade Willys from claiming, either directly or by implication, that it had created or designed the Jeep, and only allowed him to claim that it contributed to the vehicle's development. The trademark case that Bantam pursued and won was a hollow victory: by 1950 American Bantam went bankrupt, and the same year Willys was awarded the trademark "Jeep."
Except for improvements such as vacuum-powered windshield wipers, a tailgate (and thus a side-mounted spare tire), and civilian lighting, the first CJs were basically the same as the MB. The civilian jeeps also had features such as naugahyde doors, chrome trim, and were available in a variety of colours. Mechanically, a heavier transmission of the T-90 replaced the T84 of the Willys MB in order to appeal to the demographic rural buyer originally considered.
Rover had also been inspired in Britain to create their own jeep-like vehicle. Their first test vehicle was actually constructed on a Welsh farm's chassis of a destroyed war-surplus jeep and Land Rover production began after its demonstration model was well-received at the Amsterdam auto show in 1948.
Willys-Overland and its successors, Willys Motors and Kaiser Jeep continued to supply the U.S. military, as well as many allied nations with military jeeps through the late 1960s. In 1950, the first post-war military jeep, the M38 (or MC), was launched, based on the 1949 CJ-3A. It was quickly followed in 1953 by the M38A1 (or MD), featuring an all-new "round-fendered" body to clear the Willys Hurricane engine which was also new, taller. This jeep became later the civilian CJ-5 launched in 1955. Likewise, its ambulance variant, the M170 (or MDA), with a 20-inch wheelbase length, was later converted into the civilian CJ-6.
Before the CJ-5, Willys gave the public a cheaper option with the taller F-head, overhead-valve engine, in the form of the 1953 CJ-3B, by using a CJ-3A body with a taller hood. This was quickly converted into the M606 jeep (mostly used for export, through 1968) by equipping it with the available heavy-duty options such as larger tires and springs, and by adding black-out lighting, olive drab paint, and a trailer hitch. After 1968, the CJ-5 variants of M606A2 and -A3 were produced similarly for friendly foreign governments.
Licenses were given to manufacturers in many different countries for the production of jeeps, particularly CJ-3Bs, and some, such as Mahindra and Mahindra Limited in India, continue to produce them in some form or other to this day. The Jeepster is produced by Chinkara Motors of India, with FRP body. A diesel engine or the 1.8L Isuzu petrol may be supplied to the Jeepster.
In 1991 the American Society of Mechanical Engineers named the Willys-Overland Jeep MB as an International Historic Mechanical Engineering Landmark.