1935 Dodge DU Convertible Coupe: Open Coachwork on a 116-Inch Wheelbase

Dodge sold the DU passenger-car series for the 1935 model year with a 217.8-cubic-inch L-head inline-six commonly rated at 87 horsepower. The DU Convertible Coupe placed that engine, a three-speed manual gearbox, hydraulic drum brakes, and rear-wheel drive beneath folding open coachwork on a 116-inch wheelbase.

Within Chrysler Corporation, Dodge sat above Plymouth and competed directly with six-cylinder Chevrolet and Pontiac models while Ford pressed its low-priced V8 advantage. The Convertible Coupe was the costly, low-volume open body in a range dominated by practical closed sedans and coupes, which explains both its present scarcity and the number of surviving cars assembled from incomplete or mixed components.

Best known for combining Dodge's durable flathead-six running gear with a rumble-seat convertible body, the DU Convertible Coupe is one of the most visually distinctive members of the pre-war Dodge Six era.

Quick Facts

The following table separates the specifications shared across the DU family from the coachwork that defines the Convertible Coupe. Exact body-style production totals are not consistently documented in surviving summaries, so no unsupported quantity is assigned to the open model.

The DU code is the decisive series designation. The phrase Pre-War Dodge Six Era is useful as a broad historical description, but it was not a Dodge factory chassis code and should not replace DU when authenticating a car or ordering mechanical parts.

Why the Dodge DU Convertible Coupe Matters

The Convertible Coupe preserves the most specialized body configuration offered on Dodge's mainstream 1935 chassis. Its folding top, short passenger compartment, long deck, external spare-wheel treatment seen on many examples, and rumble-seat accommodation required parts that were not interchangeable with an ordinary DU sedan.

Mechanically, the car demonstrates Dodge's conservative response to a difficult market. Buyers received a large-displacement six, hydraulic brakes, a conventional separate frame, and familiar manual controls rather than an experimental drivetrain. That approach mattered during the Depression, when repairability and long service life could carry more weight than novelty.

Collector interest now follows the same distinction. A DU sedan may provide many useful engine, axle, brake, and gearbox components, but it cannot cheaply supply the convertible windshield structure, top irons, deck and rumble-seat hardware, door details, or open-body garnish moldings. A complete but weathered Convertible Coupe is therefore often a better restoration candidate than a cosmetically attractive car missing its unique fittings.

Historical Context and Development

Dodge Within Chrysler Corporation

Chrysler had acquired Dodge Brothers in 1928, and by 1935 the marque formed part of a coordinated range extending from Plymouth through Dodge and DeSoto to Chrysler. Dodge retained a reputation for robust construction while using corporate engineering and manufacturing resources. The DU arrived as American sales recovered unevenly from the deepest years of the Depression, with buyers still acutely sensitive to purchase price, fuel use, and maintenance cost.

Ford's flathead V8 was the obvious advertising challenge, while Chevrolet and Pontiac offered direct six-cylinder competition. Dodge answered with displacement, smooth low-speed operation, four-wheel hydraulic brakes, and steel body construction rather than a cylinder-count contest. There was no homologation requirement or factory competition program behind the DU Convertible Coupe; it was a road car intended for retail sale.

Styling and Body Design

The DU's appearance reflects the rapid abandonment of upright, separate-box body forms. Its grille leans rearward, the hood and cowl flow into a relatively low windshield, and the front fenders sweep back toward full-length running boards. Headlamps remained separate, while the exposed fenders and narrow body still made the chassis architecture plainly visible.

The Convertible Coupe sharpened those proportions by removing the sedan roof and concentrating visual mass over the rear axle. With the top lowered, the beltline runs almost uninterrupted from the cowl to the tail. The rumble-seat deck gives the car a longer, more formal rear profile than the business coupe, but it also introduces model-specific hinges, steps, latches, rain channels, and upholstery that complicate restoration.

Engine and Drivetrain

The DU used Dodge's water-cooled, side-valve inline-six, an engine type often described simply as a flathead six. Both camshaft and valves sit in the cylinder block, leaving the detachable cylinder head mechanically simple. The long 4.375-inch stroke favored useful torque at modest engine speed rather than high-rpm output.

A single downdraft carburetor supplied the engine through a conventional intake manifold. Ignition used a battery, coil, distributor, spark plugs, and high-tension leads, while a mechanically driven fuel pump moved gasoline from the rear tank. Pressure-fed engine lubrication, a belt-driven fan and water pump, and a cellular radiator formed the core service systems.

Power passed through a single dry-plate clutch and three-speed manual transmission to an enclosed propeller shaft and live rear axle. Period driving technique still matters: even where synchronizing assists ordinary shifts, first gear should not be treated like a modern fully synchronized ratio, and hurried downshifts can expose worn synchronizers, clutch drag, or incorrect linkage adjustment.

These are the commonly published DU engine dimensions. Torque and governed engine-speed figures are omitted because dependable, model-specific factory values are not consistently reproduced.

The 87-horsepower rating is meaningful in period context, but it should not be read as a promise of modern highway performance. The engine's virtues are its low-speed flexibility, accessibility, and ability to pull the DU without constant shifting when correctly rebuilt and tuned.

Chassis, Suspension, and Braking

The DU used separate body-and-frame construction with a conventional live rear axle. Semi-elliptic leaf springs and hydraulic shock absorbers controlled axle movement, while the front end retained a beam axle rather than modern independent suspension. Steering was by a manual steering box and linkage, with no hydraulic assistance.

Four-wheel internal-expanding hydraulic drum brakes were an important Dodge feature at a time when Ford continued with mechanical brake actuation. The system provided more even application when properly adjusted, but its single-circuit layout offers none of the redundancy associated with later dual-circuit systems.

The table concentrates on dimensions and equipment that help distinguish a DU chassis from an attractive but incorrectly described pre-war Dodge.

That chassis layout produces a high unsprung mass by modern standards, but it is predictable on smooth roads and easy to service. Worn shackles, kingpins, tie-rod ends, steering-box components, or dampers can transform ordinary period behavior into wandering, shimmy, and poor directional control.

Driving Experience and Handling Dynamics

A healthy DU starts with deliberate controls. The clutch has more travel and a firmer mechanical action than a post-war passenger car, while the long gear lever rewards a pause through neutral. The flathead six responds cleanly from low speed when its carburetor, ignition advance, and heat-management systems are correct, but acceleration diminishes well before modern engine speeds.

At parking pace, steering effort is substantial because the narrow tires still carry considerable static load through an unassisted box. Effort eases once rolling, and the long wheelbase encourages steady progress rather than rapid direction changes. Free play at the wheel should not be dismissed as normal merely because the car is old; excessive motion usually points to adjustment or wear.

The leaf-sprung beam-axle front end follows abrupt ridges and broken surfaces more actively than an independently sprung car. On roads resembling those of 1935, with moderate speeds and broad curves, the DU settles into a measured gait. Sudden steering inputs produce body roll and slow weight transfer, while the narrow tires reach their limit progressively.

Properly rebuilt hydraulic drums provide useful stopping power for the period, but repeated hard use generates heat and fade. Pulling under braking indicates adjustment, contamination, hose deterioration, drum condition, or wheel-cylinder trouble, not an unavoidable personality trait.

Identification and Originality

Serial, Engine, and Body Numbers

A 1935 Dodge does not carry a modern 17-character VIN. Authentication begins with the original vehicle serial plate, the DU series designation, engine number, body-number evidence, wheelbase, and body construction. Surviving serial plates are commonly found on the right-front door-pillar area, but placement and fasteners should be checked against Dodge service literature and undisturbed comparison cars before a conclusion is drawn.

The engine number is stamped on the block and should be recorded exactly rather than inferred from casting marks. A replacement Dodge or Chrysler flathead six may fit and function well, yet differ in displacement, date, accessories, or number sequence. The engine number is not automatically identical to the vehicle serial number, so the modern phrase matching numbers must be applied cautiously.

Collectors should inspect the body tag, frame features, wheelbase, door dimensions, cowl, windshield posts, rear deck construction, rumble-seat opening, and top mounting points as a complete system. A sedan chassis carrying fabricated open coachwork is not equivalent to a factory Convertible Coupe, regardless of the quality of the conversion.

Correct Equipment and Finishes

Originality rests heavily on parts unique to the open body: top irons, bows, header hardware, latches, windshield fittings, side-window mechanisms where fitted, rumble-seat hinges and steps, deck gutters, garnish moldings, and interior panels. Surviving cars frequently acquire later sealed-beam headlamp conversions, non-original carburetors, electric fuel pumps, alternators, modern gauges, and incorrect wheels.

Paint should be researched from 1935 Dodge color literature, body-tag evidence where applicable, and protected traces beneath trim or inside structural cavities. Generic modern interpretations of dark maroon, tan, blue, or black are not substitutes for a documented factory formulation. The same discipline applies to pinstriping, wheel color, upholstery grain, top material, plated versus painted hardware, and instrument-face restoration.

Date-coded glass, electrical components, and service replacements can support a car's history, but restorers should not discard safe, serviceable period replacements simply to manufacture a false claim of untouched originality. Bills of sale, registrations, old photographs, repair invoices, and restoration photographs usually establish provenance more convincingly than freshly reproduced tags.

Variant and Trim Breakdown

Dodge offered the DU mechanical package beneath several closed and open bodies. Catalog terminology can differ among contemporary advertisements, later reference books, and registration records, especially where a rumble-seat coupe is shortened simply to coupe.

No separate factory competition or homologation derivative of the DU Convertible Coupe is recognized. Modified cars, speedster bodies, and later hot rods should be described according to their present construction rather than represented as undocumented factory variants.

Performance and Dimensional Specifications

Factory literature emphasized engine output, wheelbase, equipment, and value rather than modern acceleration testing. Dependable model-specific 0-to-60-mph, quarter-mile, and top-speed figures for the Convertible Coupe are not sufficiently consistent to present as fact.

Published shipping or curb weights can differ according to equipment, fuel allowance, spare-wheel installation, and the terminology used by the source. For restoration, spring selection, or transport planning, an actual scale weight is more useful than transferring a sedan figure to the Convertible Coupe.

Compared With Related Dodge Models

1934 Dodge DR and 1935 DU

The preceding 1934 Dodge passenger range belongs to a different series and should not be treated as a source of automatically interchangeable body parts. Styling, chassis details, trim, and serial identification changed even where the underlying flathead-six principles appear familiar. Buying a 1934 donor solely because its panels look close can become an expensive mistake.

1935 Dodge DU and Plymouth PJ

The Plymouth PJ served a lower price class within Chrysler Corporation. Both cars used conventional front-engine, rear-drive layouts and flathead six-cylinder power, but the Dodge carried a larger 217.8-cubic-inch engine and a 116-inch wheelbase. Corporate resemblance does not guarantee interchangeability among sheet metal, trim, axle components, brakes, or engine accessories.

1935 DU and 1936 Dodge D2

The 1936 D2 succeeded the DU and is regularly confused with it in advertisements for cars and parts. The D2 has its own serial sequence, styling details, and model-year components. A title describing a car as a 1935 or 1936 based only on first registration can be misleading, so the serial plate and physical specification must decide the model year.

Ownership and Restoration Notes

Routine mechanical parts for Chrysler-built flathead sixes are generally easier to source than Convertible Coupe body hardware. Ignition components, carburetor kits, bearings, gaskets, brake parts, and cooling-system items have long benefited from interchange and specialist support, although every component should be ordered by casting number, dimensions, and application rather than by appearance.

Flathead-six rebuilding requires careful measurement. Common concerns include cylinder wear, valve-seat recession or damage, cracked blocks around valve seats or water passages, corroded water-distribution components, blocked cooling jackets, low oil pressure, and poorly repaired exhaust-manifold studs. The long cylinder head also demands a flat sealing surface, correct fasteners, proper tightening sequence, and heat-cycle retorquing where specified by the gasket supplier.

The cooling system deserves particular attention because sediment can remain after an ordinary radiator flush. Overheating may result from a restricted block, damaged water-distribution tube, tired pump, incorrect ignition timing, lean mixture, collapsed hose, unsuitable radiator core, or missing airflow hardware. Installing a larger electric fan does not cure the underlying fault.

Gearbox noise can arise from bearings, gears, shaft wear, lubricant choice, or clutch misalignment. Rear-axle whine deserves diagnosis before disassembly because ring-and-pinion setup requires suitable measuring tools and experience. Brake cylinders and old flexible hoses should be treated as safety items, particularly on a car that has sat unused.

Structural restoration is the greater financial risk. Inspect the frame around crossmembers, suspension mounts, steering-box attachment, rear kick-up, body brackets, and previous welding. The open body also depends on sound sills, door posts, cowl structure, floor edges, and rear body framing to keep its door openings square.

Buyer and Inspection Points

A proper inspection should establish identity and completeness before evaluating paint quality. Missing convertible components can exceed the cost of an engine overhaul because replacements may need to be copied from another car or fabricated individually.

A road test should begin with the engine fully cold and continue until the cooling system has stabilized. Check the car again after shutdown for heat soak, fuel leakage, coolant discharge, clutch behavior, and hot starting. Fresh paint cannot compensate for a fabricated body identity, incomplete top mechanism, or structurally weak sill assembly.

Collector and Market Relevance

Desirability within the DU family generally favors the Convertible Coupe because few open cars survived weather, wartime scrappage, neglect, and later modification. Exact production figures for this body are not consistently documented, but the disparity between surviving sedans and authentic open cars is readily apparent in club registries, restorations, and auction catalogues.

Collectors place the greatest value on a verifiable factory body, complete top and rumble-seat equipment, correct DU mechanical specification, sound documentation, and restoration work that respects original materials and finishes. A replacement engine does not automatically disqualify a car, particularly when documented, but an undisclosed later engine or recreated identity materially changes how the car should be judged.

Modified DU convertibles have their own audience, especially where later V8 engines, hydraulic upgrades, or street-rod chassis work are executed well. They belong to a different market from accurately restored examples. Reversing extensive modification is rarely economical if the original frame, firewall, instruments, suspension mounts, and driveline have been removed.

Cultural Relevance

The DU Convertible Coupe reflects an American body style that largely disappeared after the 1930s. Its rumble seat placed occasional passengers outside the main cockpit, while its folding roof delivered open-air motoring without the size and price of a formal convertible sedan. That arrangement now defines the car visually as strongly as its Dodge grille or exposed fenders.

The model has no major factory racing or homologation legacy. Its historical value instead comes from road use, preservation, marque-club activity, and the long-running American restoration and hot-rodding cultures that kept many pre-war Dodge chassis in circulation. Period photographs, local parade records, family ownership histories, and club documentation can therefore add meaningful context to an individual car.

Frequently Asked Questions

What engine is in the 1935 Dodge DU Convertible Coupe?

It uses a naturally aspirated 217.8-cubic-inch Dodge L-head inline-six, commonly rated at 87 horsepower at 3,600 rpm. The engine drives the rear wheels through a single-plate clutch and three-speed manual transmission.

What does the DU code mean on a 1935 Dodge?

DU is the Dodge passenger-car series designation for the 1935 model discussed here. It is more useful for authentication and parts research than broad descriptions such as pre-war Dodge Six, which cover many unrelated models.

How can a genuine DU Convertible Coupe be identified?

Inspect the vehicle serial plate, engine number, body-number evidence, 116-inch wheelbase, title, cowl and windshield structure, door openings, rear deck, rumble-seat arrangement, and factory-style top mounting points. No single loose tag proves that a body began life as a Convertible Coupe.

Did the 1935 Dodge DU Convertible Coupe have a rumble seat?

The cataloged Convertible Coupe used rear deck accommodation commonly described as a rumble seat. Its lid, hinges, steps, latch, gutters, seat frame, and trim are among the most important pieces to verify on a restoration candidate.

Are parts available for a 1935 Dodge DU?

Many flathead-six service parts, brake components, bearings, ignition items, and carburetor kits remain obtainable through specialist suppliers. Convertible-only sheet metal, top irons, garnish moldings, rumble-seat hardware, and correct trim are much harder to find.

What are the principal known problems?

Check for cooling-jacket restriction, damaged water-distribution parts, cylinder and valve wear, block cracks, low oil pressure, gearbox and axle noise, hydraulic-brake deterioration, steering play, worn spring shackles, frame repairs, and corrosion in the open body's sills and door posts.

What most affects restoration cost and collector value?

Body authenticity, structural condition, completeness of convertible hardware, rumble-seat equipment, grille and trim quality, engine condition, and documentation have the greatest effect. Missing body-specific components can cost more to rectify than rebuilding the shared mechanical units.

Collector Takeaway

The 1935 Dodge DU Convertible Coupe matters because it preserves Dodge's mainstream 217.8-cubic-inch six-cylinder engineering in the body least likely to survive intact. Its engine, gearbox, brakes, and axles can be repaired with established pre-war Chrysler knowledge, but its folding top, rumble-seat deck, open cowl, and structural hardware demand a much higher level of archaeological care.

The best example is not necessarily the one with the brightest paint. It is the car whose DU identity, factory open body, top mechanism, rear-seat hardware, and ownership record agree with one another. When those pieces remain intact, the Convertible Coupe explains 1935 Dodge more clearly than any catalog slogan: durable six-cylinder machinery underneath, specialized American open coachwork above, and no unnecessary complication between them.