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  • Writer's pictureTedd Long

Who's Your Daddy?

Meet Barney Roos—One of Many Jeep Daddies

Willys MB

Some say that General George Marshall was the "Father of the Jeep" since he made the most noise about the American Army's need for an all-terrain vehicle after his mud-spattered experiences with mules and horses during World War I. While it's true that Marshall played a crucial role in the government's investment in a motorized vehicle to replace the horse and, in due course, approved the testing and production of the jeep, singling him out as the "patriarch" of the iconic SUV is an oversimplification of a very complex story. The fact is, the jeep had multiple daddies.

American Bantam Print Ad circa 1938

In early 1940, with tangible signs of our involvement in the war in Europe on the horizon, the U.S. War Department issued a request for proposal to over 135 U.S. carmakers for a ¼-ton reconnaissance vehicle. In response, Karl Probst, a freelance automobile designer from Detroit, was hired to draw up plans developed by Harold Crist, Ralph Turner, and Chet Hemphling of American Bantam Car Company of Butler, Pennsylvania. The tight timetable outlined in the U.S. government's proposal only allowed for a 50-day window to create a prototype after contract signing, so Bantam didn't waste any time. In fact, Probst's drawings for the 1,840-pound Bantam "Blitz Buggy" took only 18 hours, and Bantam cranked out the prototype in time for the government to test by September of 1940. Remarkably, even with the rush, the vehicle exceeded the Army's expectations. However, while the War Department was enthusiastic about the Blitz Buggy, they had significant reservations about Bantam's ability to meet their production quotas. As a result, Ford and Willys-Overland were invited to re-bid on the Army's requirements using Bantam's design as a guide. By July of 1941, after first proposing their Quad and then the MA, the Willys-Overland MB won out as the War Department’s top choice. Besides adding a lower-cut silhouette, a feature favored by General Marshall, what set the Willys-Overland proposal apart from Ford was the strength of its 60 horsepower "Go Devil" 4-cylinder engine, in spite of its extra weight.

The Go Devil engine was the most powerful of the three prototype vehicles evaluated by the US Army for production. In the end, Bantam was given a contract to produce quarter-ton trailers to be towed behind the MB, and Ford was contracted to assist Willys-Overland due to an increased demand for production. By 1945, the Willys MB and her Ford GPW counterpart proved to be what General Marshall said was "America's greatest contribution to modern warfare." Between Willys and Ford, total jeep production reached 634,569 units for the US military and all allies. From this, Willys-Overland produced 354,569 of the type with the rest handled by Ford.

But what about this “Go Devil” engine—the heart of the jeep. Wouldn’t the mastermind behind the jeep’s dynamo count as one of its daddies? I think so. The Go Devil engine was developed in-house by Willys' Chief Engineer, Barney Roos. Before his work at Willys-Overland, Roos had built a global reputation as a talented automotive engineer.

Delmar Gerle Roos was born in New York City on October 11, 1888. He attended Manual Training High School in Brooklyn. He picked up the nickname “Barney” while attending Cornell University because of his devotion to his racing idol Barney Oldfield. While earning degrees in mechanical and electrical engineering at Cornell, he developed a solid reputation as an accomplished news photographer, who had a famous photo circulated on the national wire service, and athlete after winning the intercollegiate and national fencing championships.

After graduation, Roos enjoyed brief stints as a press photographer and assistant to Dr. Sanford Moss at General Electric’s Steam Turbine Department in Lynn, Massachusetts. He began his work in the automotive field in 1913 as an assistant research engineer at Locomobile. During World War I, Locomobile sold the Riker Truck to the British Army, contributing more vehicles to the war than any other American company. After the war, Roos moved to Pierce-Arrow in 1919 and then back to Locomobile as Chief Engineer in 1922, where he helped lead the design of a new straight-eight engine. He then moved on to Marmon, where he led the development of a small straight-eight—similar to the Locomobile design. In 1926, Roos was named Chief Engineer at Studebaker. From 1936 to 1937, during a temporary assignment to England with the Rootes Group, which distributed Studebaker products in the U.K., Roos cultivated an interest in delivering more power for smaller cars with smaller engines.

In 1938, Roos accepted Ward M. Canaday’s offer to become the Executive Vice President and Chief Engineer at Willys-Overland. With years of engineering experience behind him and his recent involvement in drawing more power from smaller engines, Roos was the perfect choice by Canaday to redo the anemic 30 hp Willys four-cylinder engine initially designed for the 1926 Whippet. To modernize the engine, Roos incorporated a fully counterbalanced crankshaft, aluminum pistons, insert bearings, and a new lubrication system and valvetrain. In just a few months, the new engine was putting out 60 hp at 4,400 rpm. The new engine was dubbed Go-Devil and first appeared in some of the 1939 Willys cars rated at 61 hp at 3600 rpm. This same Go-Devil four-cylinder engine became the heart of the U.S. Army's World War II jeep.

The Go-Devil enjoyed a long life. It powered military jeeps from 1941 to 1952, was used in civilian 4x4 Jeeps from 1945 to 1954 and in the DJ 4x2 Jeeps through 1964. The Jeep station wagons and trucks used them until mid-’50s. They were also used as commercial, marine and generator engines. As for the jeep, it became one of the most emblematic cars and iconic brands in the world.

This long-term success of the Go Devil engine and the jeep went well beyond what Barney Roos envisioned in 1943 when he was asked about the future of the military vehicle in an interview with the Toledo Times. He said:

Certainly the jeep is not going to affect the passenger car, because no one wants a four-wheel drive passenger car that has big tires and is a hog on gasoline. It would eat up tires and gasoline and would be expensive. But it may profoundly affect the agricultural truck. It has great possibilities in agriculture where a small farm is involved, where you don’t have your money tied up in a truck and in a tractor or in a power plant. When the war ends there will be many thousand of these jeeps that can be bought from the government at low prices by the farmers.”

Barney Roos, left Willys after Kaiser acquired the company in 1953, but continued to consult for them until his retirement in 1958. He passed away suddenly in 1960 at the age of 72. The jeep story may be a complicated one, but in the end, Barney Roos will go down in history as one of many fathers of the famous SUV.

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