After Cord's takeover, the new company was renamed "Duesenberg, Inc." Fred would continue in the new organization, now with the title of vice president in charge of engineering and experimental work. Whereas Augie had played an important role in the development of the Model A and its variant, the very rare X, he had nothing to do with the J and had no formal connection with Duesenberg, Inc. until later. According to the expert Marshall Merkes, "Cord did not want Augie around". However, all Duesenberg racing cars produced after 1926 were Augie-built in an enterprise that functioned separately, and in a building apart from the main Duesenberg plant. He was also responsible for a number of engineering achievements like the superchargers he developed for both the Auburn and Cord motorcars.
The first Model J prototype, created in February 1927, was the Model Y. Two such cars were built with engines of 320 cu in (5.2 l). One of these engines had single overhead cam and the other had a double overhead cam. It was Fred’s thinking that lighter, smaller cars with higher rpm engines would be the ideal configuration. Cord did not agree, and as it was his dream, he nixed the prototype Model Y after road-testing. The next prototype was the Model H, which exists only on paper and varies only slightly from the later Model J.
In February 1928 the Model J designation was born. The newly revived Duesenberg company set about to produce the Model J, which debuted for the first time on December 1 at the New York Car Show of 1928. In Europe, it was launched at the "Salon de l'automobile de Paris" of 1929. The first and — at the time of the New York presentation - only example made of the series, the J-101, was a LeBaron sweep panel dual cowl phaeton finished in silver and black.By the time the Great Depression hit in October 1929, the Duesenberg Company had only built some 200 cars. An additional 100 orders were filled in 1930. Thus, the Model J fell short of the original goal to sell 500 cars a year.
The straight eight model J motor was based on the company's successful racing engines of the 1920s and though designed by Duesenberg they were manufactured by Lycoming, another company owned by Cord. In unsupercharged form, it produced an impressive (for the period) 265 horsepower (198 kW) from a dual overhead camshaft and four valves per cylinder. It was capable of a top speed of 119 mph (192 km/h), and 94 mph (151 km/h) in 2nd gear. Other cars featured a bigger engine but none of them surpassed its power. It was also both the fastest and most expensive American automobile in the market. All these unique features, glamour, and style inspired the expression, "It's a Duesy".
As it was custom among the luxury car brands, only the chassis and engine were displayed, since the interior and body of the car would be custom-made by an experienced coachbuilder to the owner's specifications. The chassis on most model J's were the same, as was the styling of such elements as fenders, headlamps, radiator, hood and instrument panel.
The bodyworks for the Duesenbergs came from both the U.S. and Europe, and the finished cars were some of the largest, grandest, most beautiful, and most elegant cars ever created. About half the model Js built by Duesenberg had coachworks devised by the company's chief body designer, Gordon Buehrig, the rest were designed and made by independent coachbuilders from the U.S. such as Derham, Holbrook, Le Baron, Murphy, Rollston (later renamed Rollson), Walker, Weymann, and Willoughby, to name a few and from Europe; Fernandez et Darrin, Franay, Gurney Nutting, Saoutchik, etc. However, other coachworks were made by Duesenberg branches in Chicago, New York City, Los Angeles, Philadelphia, Florida and Denver, as well as by smaller dealers. For the in-house bodies Duesenberg used the name of La Grande.
The chassis cost $8,500 ($9,500 after 1932); the completed base model cost between $13,000 and $19,000 (two of the American-bodied J's reached $25,000), at a time when the average U.S. physician earned less than $3,000 a year. Figures are not available as to the prices charged by deluxe coachbuilders in Europe, but it is reasonable to assume that the final selling price of the products mounted on the costly imported chassis were considerably higher than their all-American-built counterparts.
The J was available in two versions of chassis with a different wheelbase; a long one (153.54 in (3.90 m)) and a short one (about 141.73 in (3.60 m)). There were also other special sizes; like the only two SSJ's with a wheelbase shortened to 125 in (3.18 m) and a couple of cars with the wheelbase extended to 4 m (160 in) and over.
The dash included lights that reminded the driver the oil needed changing and the battery should be inspected.
A series of minor modifications were carried out during the production life, but most of the design remained the same up until the factory closed in 1937. First to go was the four-speed gearbox, which proved unable to handle the engine's power. It was replaced by an unsynchronised 3-speed gearbox, which was fitted to all subsequent Duesenbergs. Unlike almost all American manufacturers, Duesenberg did not switch to a fully synchronised gearbox in the mid-1930s, which made the Model J difficult to drive and outdated. By 1937 the chassis and gearbox were ancient compared to the competition.
Regarding this model, it is necessary to emphasize that most of them (engine and chassis) were made in 1929 and 1930, but due to the Depression, high price, etc., were sold throughout the next years. To date a certain J it is taken the year a car was bodied, even though the chassis were made in 1929, 1930, etc.
The model J was modified and is known as the Duesenberg " SJ " (a name never used by the company) it was a supercharged version and was reputed to do 104 miles per hour (167 km/h) in second and have a top speed of 135–140 mph (217–225 km/h) in third. Zero-to-60 mph (97 km/h) times of around eight seconds and 0–100 mph (0–160 km/h) in 17 seconds were reported for the SJ in spite of the unsynchronized transmissions, at a time when even the best cars of the era were not likely to reach 100 mph (160 km/h).
Duesenbergs generally weighed around two and a half tons; up to three tons was not unusual, considering the wide array of custom coachwork available. The wheelbase was 142.5 inches. This rare supercharged Model J version, with 320 hp (239 kW) was also created by Fred Duesenberg and introduced in May 1932, only 36 units were built.
Special-bodied models, such as the later "Mormon Meteor" chassis, achieved an average speed of over 135 mph (217 km/h) and a one-hour average of over 152 mph (245 km/h) at the Bonneville Salt Flats, Utah.
The SJ's supercharger was located beside the engine; to make room for it, the exhaust pipes were creased so they could be bent easily and extended through the side panel of the hood.
These supercharged cars can be recognized by these shiny creased tubes, which Cord registered as a trademark and used in his other supercharged cars from Cord and Auburn.
It was said, "The only car that could pass a Duesenberg was another Duesenberg—and that was with the first owner's consent."
Fred Duesenberg died of pneumonia on July 26, 1932, resulting from injuries sustained in an automobile accident in which he was driving a Murphy SJ convertible. His brother, Augie, took over Fred's duties as chief engineer.
The SSJ is very similar to the SJ version, but with a horsepower close to 400 hp (298 kW). The only two examples built in 1935, the SSJ Speedsters sported a lightweight open-roadster body produced by Central Manufacturing Company, an Auburn subsidiary in Connersville, Indiana. One of them belonged to the actor Gary Cooper, the other one was lent by the company to Clark Gable, who already owned a Duesenberg J. The inscription SSJ (same goes for SJ) has never been officially used by the company but it eventually became commonly used among the car lovers. The second "S" stands for "short wheelbase" as the two SSJ; are the only Duesenberg to have a chassis with the wheelbase shortened to 125 in (3,200 mm). The 420 cu in (6.9 l) straight eight engine of both SSJ models is equipped by two special carburetors and inlet ports of a special shape called "ram's horn", which was used in other SJ's as well. Unlike the normal port, the "ram's horn" is composed of two horns and each of these then splits in two again. At the rear, the SSJ sported an external spare tire and smaller “later-style” round taillights. The external exhaust pipes sprouting out of the hood were an indication it was the “supercharged” version, but these were optional on J models as well.
Another version of the model J known as the Duesenberg " JN " (again a name never used by the company).
All JN's were sold with Rollston coachwork and only 10 were produced in 1935.
In an attempt to give a more modern look to an aging design, the JN was equipped with smaller 17-inch-diameter wheels (versus 19 inches), skirted fenders, bullet-shaped tail lights, and bodies set on the frame rails for a lower look.
The battery box and tool box were redesigned slightly so that the doors could close over the frame.
Those Duesenberg JN's that were Supercharged, a total of only 5 and all produced in 1936, gained the logical Duesenberg " SJN " designation.
The Duesenberg quickly became one of the most popular luxury cars as well as a status symbol in the United States and Europe, driven by the nobility, rich and famous, among them Clark Gable, Gary Cooper (each driving one of the two very rare SSJ 125″ short-wheelbase convertibles), Al Capone, Evelyn Walsh McLean, Greta Garbo, Howard Hughes, Mae West, Marion Davies, Tyrone Power, Bill "Bojangles" Robinson, William Randolph Hearst, the families Mars, Whitney, Wrigley.
Also members of the European royalty such as the Duke of Windsor, Prince Nicholas of Romania, the Queen Maria of Yugoslavia, the Kings Victor Emmanuel III of Italy and Alfonso XIII of Spain.The latter was very keen on motoring and chose his now missing Duesenberg J, among his cars, to go to exile after the proclamation of the Second Spanish Republic.
Father Divine had the last Duesenberg chassis built with an extra-long 178-inch wheelbase. It weighed 7,800 lbs and accommodated ten passengers. J. Herbert Newport was the designer. Built by Bohman and Schwartz and delivered in October 1937, it was 22 feet long and seven feet wide. It was known as "Father Divine's Throne Car" because it had a removable rear top section that exposed two raised rear seats.
Originally, New York supported the Model J. New York was the financial capital of the United States in 1929, and many of its people could afford such a very expensive car. As the Depression deepened, however, power shifted, and ultimately it was newly wealthy Hollywood that kept Duesenberg alive through much of the 1930s. It was so reputed and imposing that many Hollywood stars, such as James Cagney, posed next to the car to promote their careers.
Duesenberg advertising the Model J as "The World's Finest Motor Car". In their print ads, an elegant man or woman were seen together with a concise but meaningful sentence: "He/She drives a Duesenberg". The campaign was a success.
There was a gradual evolution (up to the 1937 model) to preserve the "stately lines" while moving into a more integrated mode of styling. The final evolution of the Duesenberg engine was ram-air intakes, which were added to some of the last supercharged models to produce 400 hp (298 kW), referred to as "SSJ". Of the 481 Model J's (including all its versions) produced between 1928 and 1937, about 378 survive.
Duesenberg ceased production in 1937 after Cord's financial empire collapsed. However, between 1937 and 1940 two automobiles put the final touch to this historical marque. The first one was delivered by the coachbuilder Rollson to the German artist Rudolf Bauer in April 1940; it is both the longest Duesenberg and the last one delivered. The last one ever made was assembled from leftover parts between 1938 and 1940.
Duesenberg became far less popular during World War II, by the end of which a few Model J's were sold for only $100 or $200. Business rebounded in the 1950s, when classic and vintage cars became popular among collectors.