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The Mighty Jeep

July 2024
8min read

Rugged, versatile, and nearly indestructible, this four-wheel substitute for the horse has become one of World War II’s enduring legends

A few weeks before Pearl Harbor, the highest ranking officer in the Armed Forces, General George C. Marshall, described as our main contribution to modern war a new, small, bouncy army vehicle with the official designation of truck, quarter-ton, four-by-lour, but better known to practically everyone, then and now, as the jeep.

No one is certain exactly where the name “jeep” came from. The most widely accepted theory is that it originated in the pronunciation of the army designation G. P., meaning “general purpose,” but at one time or another it has been used to refer to an experimental railroad engine, a three-ton tractor, an autogyro, and a careless soda jerk. The question is further confused by the fact that in the prewar army, especially in the Armored Force, the quarter-ton four-by-four was called not a “jeep” but a “peep,” the former term being reserved for a larger command-and-reconnaissance car.

At any rate, this diminutive, versatile, and supremely practical machine became one of the memorable symbols of American participation in World War II. It was a kind of military Model T, embodying the best elements of Yankee tinkering and functional design. Little in civilian life could have prepared the millions of soldiers and sailors for the jeep’s uniform olive-drabness, its squat boxy shape, and its stripped-down simplicity; yet none could have failed to recognize it immediately for the characteristically American product that it was.

The jeep was a no-nonsense solution to a specific wartime problem. Its low silhouette, when the canvas top and the windshield were put down, was meant to make it usable in the front-line area. Its four-wheel drive enabled it to negotiate soft ground and climb grades that would have defeated an ordinary car. It could operate without strain from three to sixty m.p.h. and climb a forty per cent grade; and it was virtually indestructible. Major General Eugene Reybold, Chief of Engineers, a notoriously conservative branch of the Army, once said that in all his travels he had “never seen a jeep that wouldn’t run.”

In its first large-scale maneuvers, in Louisiana in September, 1941, the jeep completely stole the show, pulling antitank guns into positions where “enemy” tanks had not expected to find them; and in the North African landings—the first major combat operation for the jeep—it proved itself time and again. It was the only fast vehicle that could operate in rough desert terrain. Perhaps the most dramatic jeep offensive action of the war was an attack on enemy aircraft led by David Stirling, the “phantom Major,” commander of a British raiding force organized around the jeep as basic transportation. The target was Landing Ground 12 at Sidi Haneish, seventy miles west of El Alamein.

Each jeep was armed with four Vickers K machine guns capable of firing one thousand rounds a minute. Formed in flying wedge, the jeeps charged out of the desert onto the airfield between the rows of parked planes, all guns blazing. After one complete circle of the airfield they attacked planes parked on the perimeter; then they roared away into the comparative safety of the desert. The score: twenty-five planes destroyed, and a dozen damaged. The attacking force: seventy-five men and eighteen jeeps.

As the war progressed the jeep’s versatility seemed endless. Fitted out with stretchers, it became a frontline ambulance. A jeep plus a radio was a mobile command post. Jeeps hauled planes to dispersal bunkers. Soldiers raced them uphill, as in a famous cartoon by Bill Mauldin, to get hot radiator water for shaving. In the Philippines a jeep equipped with flanged wheels pulled a fifty-two-ton railroad supply train for nineteen miles at twenty miles an hour. When Patton’s armored divisions raced across France the lead vehicle, out in front of the foremost tanks, was often as not a jeep.

One of the permanent items of wartime mythology is the odyssey of two reporters, Daniel DeLuce and Darrell Berrigan, who drove their jeeps 1,300 miles out of Burma into India after the Japanese capture of Mandalay. On their arrival in Imphal, it was pointed out to them that there must be some mistake, since there were no roads in the area they had crossed. “Sh-h! Not so loud,” the Chicago Daily News quoted one of them as saying. “Our jeep hasn’t found out about roads yet, and we don’t want to spoil it.”

All things considered, it is not surprising that the jeep attained a unique place in the affection and confidence of the men who used it. What is surprising, and gives a special flavor to the jeep legend, is the intensely personal quality of the feelings it aroused. There is even a story of a corporal, found sitting in the charred wreckage of a jeep that had been shelled, who refused to be comforted by assurances that he would get a replacement, “But you don’t understand,” he said, between sobs, “I loved this one.”

The jeep was a vehicle for the young. At least you had to be limber and resilient to get in and out. or to survive many miles of jeep-borne travel. (The contortions required to climb into a jeep, for tight-skirted WACs and WAVEs, were a source of never-failing interest to admiring GIs.) There were only two ways to sit in a jeep, either bolt upright or slouched down to the middle of the backbone, and after a few hours neither was particularly comfortable. But jeeps were treated like treasured possessions, nonetheless. You couldn’t lock a jeep, since it had a small ignition switch in place of a key, and so you either had to chain it up or remove the distributor head. Enterprising jeep thieves were likely to carry spare distributor heads of their own.

The heart of the jeep was its engine, and the man who made that heart tick was the late Delmar G. Roos, known to automotive engineers as Barney. Barney Roos had designed a 100-mile-an-hour Locomobile staff car in World War i. Later he became chief engineer for Fierce-Arrow, Marmon—where he designed the Marmon Straight 8—and Studebaker. When he came to Willys early in 1938 he was shown a four-cylinder engine that was being used in a Willys light car, and given the job of improving it.

What Barney Roos wanted was an engine that could develop (15 horsepower at 4,400 r.p.m. and run for 150 hours without failure. What he started with was an engine that developed 48 horsepower at 3,400 r.p.m., and could run continuously for only two to four hours. (For comparison, a 1939–40 Ford developed 60 horsepower at 3,500 r.p.m.) It used oil excessively, its bearings wore out fast, the water pump and cylinder head leaked, it shook loose its starter, and it had a congenital pre-ignition knock.

It took Barney Roos two years to perfect his engine, by a whole complex of revisions that included closer tolerances, tougher alloys, aluminum pistons, and a flywheel reduced in weight from fifty-seven to thirty-one pounds. He had also heard, by the time the job was done, that the Army was interested in a light vehicle. A homemade product called the “belly-Hopper,” a low springless platform on nine-inch airplane wheels, had in fact been built by Colonel Robert G. Howie and Master Sergeant Melvin C. Wiley. “It looked,” Roos said, “like a diving board on wheels.” It was too light for really rough terrain. It had to be transported from point to point by truck. It had virtually no ground clearance. But it was easy to conceal—and, above everything else, it had the power to stimulate the imagination.

Roos described his own ideas for a low-silhouette vehicle to Major General Walter G. Short, later to have the misfortune of commanding at Pearl Harbor. The Army had appointed a technical committee, which had tested small cars made by the American Bantam Company and arrived at specifications for a military vehicle. These called for four-wheel drive and a low speed of three miles an hour. Top weight was to be 1,000 pounds with a Goo-pound pay load. The first seventy vehicles were to be delivered within seventy-five days. Bids were requested of 135 manufacturers, but only two of them were interested, Bantam and Willys.

The Bantam response must have been one of the fastest on record. Plans and a bid were submitted in less than a week, and the first pilot model was completed in forty-nine days. Willys had asked for an extension of the contract time, and had been refused. Barney Roos knew the weight limit was impossible for his engine, but he also knew no similar engine was available that could match his for endurance and performance. He wanted to show the Army what Willys could do. Prodded, the Quartermaster Corps invited Willys to develop a model at its own expense and agreed to test it.

The Army drivers at Camp Holabird expected to make short work of the Willys model, but they were considerably surprised. The Willys’ test set even higher standards of performance than Bantam’s. There was only one flaw: the Willys jeep weighed 2,423 pounds, far over the target of 1,600. Specifications for new bids raised the maximum, including oil and water, to 2,175 pounds, but Willys was told to get under that limit or forgo future orders, and Ford too was asked to participate.

Barney Roos now had to decide whether to scrap his tough engine and buy a lighter and less powerful one on the open market, as Bantam had done. He decided not to, and so the ordeal of reducing weight began. Body and chassis were stripped and every part studied. First, all unnecessarily long bolts were shortened. Then the thickness of the steel was reduced on body and lenders. Tough alloys were substituted in the frame for heavier carbon steel (aluminum and magnesium were unavailable). Reinforcing plates were reduced. New paints were tested and spray methods analyzed; eventually nearly ten pounds of paint were eliminated! Pound by pound, and then ounce by ounce, the weight came down. When the slenderized model was assembled it weighed 2,164 pounds. Willys was in.

The first vehicles to come from Ford, Bantam, and Willys were tested by all the interested units, but the report of the Infantry Board is representative of the rest: “Willys performance was superior to that of Bantam and Ford in acceleration, maximum speed, grade climbing and cross country. The reason lies in its greater horsepower and torque … engine, transmission, frame …”

The report concluded that “the standard vehicle should be based upon the Willys chassis, with the Ford shift lever and hand brake arrangement, and the power and performance characteristics of the Willys.” ft was clearly a triumph for Willys’ design and for Barney Roos’s pet engine.

Bantam soon dropped out of the running. Edsel Ford tame to pick up the Willys’ blueprints, and Ford and Willys settled down to the job of turning out 651,068 jeeps for the war effort. With the 2,500 produced by Bantam, the total of military jeeps came to 653,568.

The wartime performance of the jeep had naturally stimulated interest in its potential postwar uses. Before the fighting was over the Department of Agriculture had already begun publicizing alluring jeep solutions to farm labor problems. The Agriculture people had concluded that the jeep could plow, harrow, or disc; plant corn or cotton, all on one gallon of gas to the acre—claims that were later far exceeded in practice. As a result, civilian desire to own a jeep was widespread by the time the first combat-weary vehicles were put on the market in November, 1943.

These original jeeps have gone on performing. From time to time the Egyptian Army has dug up a jeep from the desert sands where it had been buried ten years or more, but nonetheless has quickly put it in combat condition. Only a short time ago a sergeant in the 37th Infantry motor pool in Aschaftenburg, Germany, traced a low-number engine in one of his jeeps back to the North African campaign fifteen years earlier. The body had only been through the Korean war and was therefore practically brand new.

The day of the jeep is still not over. Today it is faster and more powerful than ever. About 100,000 a year are produced in the U.S.A. alone, and they may be found nearly anywhere. The United Nations Children’s Fund, for example, has put about 2,500 in service on lour continents. During the international Geophysical Year jeeps operated successfully in Antarctica, the only wheeled vehicles in the Navy’s expedition. In India during the 1957 elections, the Nationalist party in one state where the outcome was doubtful scored a coup by cornering for its candidates all available jeeps. Jn Mexico on several haciendas where animals are bred for the bull ring, durable jeeps are used instead of perishable horses to test the fighting qualities of the young bulls.

But the jeep’s military outlook is not bright. U.S. Army orders have trickled away to nothing. For some years the Army had been after Ford to develop an improved quarter-ton four-by-four, and in June, 1959, production orders were finally issued. The new vehicle has already been nicknamed, with something less than inspiration, the Mutt—which stands for Military Utility Tactical Truck, it is undoubtedly more capable, more comfortable, and more admirable in many respects, but it isn’t the jeep—and those of us who loved that venerable vehicle will not be fooled, or comforted.

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