Car Collector International
Classic · 1928–1937

Duesenberg Model J / SJ

America's grandest pre-war motor car — 6.9-litre DOHC straight-eight, supercharged SJ, and the most theatrical coachwork in the world.

Car Collector International Editorial
Maroon Duesenberg Model SJ convertible coupe with tan soft top raised, front three-quarter studio view on a plain grey backdrop showing external supercharger exhaust pipes, chromed grille and whitewall tyres.
Overview

Why this car matters

The Duesenberg Model J (1928–1937) was the most ambitious American car of the pre-war era. Powered by a 6,882cc twin-overhead-cam straight-eight producing 265 bhp (or 320 bhp with the Roots-type supercharger fitted to the SJ from 1932), the J chassis was rolled to coachbuilders including Murphy, Derham, LeBaron, Rollston, Willoughby, Bohman & Schwartz and Walker. Approximately 481 chassis were built; the SJ accounts for around 36 cars. Owners included Clark Gable, Gary Cooper, Mae West and Greta Garbo.

Defines American pre-war grand luxury. Original SJ cars and SSJ short-chassis Roadsters are at the very top of the world market.

Variants

Range and production

VariantYearsProductionNotes
Model J1928–1937445Naturally aspirated DOHC straight-eight.
Model SJ1932–193736Roots-supercharged; 320 bhp.
Model SSJ19352Short-chassis Roadster; Clark Gable / Gary Cooper.
Buyer's Guide

What to look for

Provenance and originality

For pre-war and vintage cars such as the Duesenberg Model J / SJ, provenance is paramount. Chassis and engine number matching, period coachbuilder records, factory build sheets where available, continuous ownership documentation, original handbooks and any competition or concours history are the foundation of value. ACD Club Category 1 certification (verified original chassis, engine and coachwork), coachbuilder, body style and continuous history.

Mechanical inspection priorities

The DOHC inline-eight is sophisticated and robust; the supercharger raises stress and rebuild costs. Original engines and chassis matched per ACD Club records carry premium. A pre-purchase inspection by a recognised marque specialist should include compression and leak-down testing, magneto and ignition checks, chassis straightness and frame survey, axle and steering wear assessment, brake system review (mechanical or hydraulic per period), and an extended road test on varied terrain to expose carburation, cooling and gearbox issues that only emerge under sustained running.

Body, chassis and originality of coachwork

Pre-war coachwork is rarely truly original after a century of use. Establish whether the body is original to the chassis (period photographs, build records, coachbuilder plates), whether it has been re-bodied at any point, and the standard of any restoration. Quality of timber framing, ash health, panel beating and paint depth are all critical. Concealed structural rot, re-bodies presented as original, and 'tribute' cars built on later or unrelated chassis must be priced accordingly.

Specification and event eligibility

SSJ short-chassis Roadsters and original SJ supercharged cars lead by an enormous margin; Murphy-bodied convertibles and Bohman & Schwartz Speedsters follow. ACD Club Category 1 certification underpins eligibility for the club's Reunion at Auburn and for CCCA Grand Classic events, and top cars anchor the pre-war American classes at Pebble Beach and Amelia Island. Confirm the car's ACD Club standing and concours history before purchase.

Ownership

Living with it

Typical mileage
300–2,000 miles typical for vintage use; rally cars higher
Service interval
Annual full service; pre-event check before any rally or tour
Annual running cost
$8,000 – $35,000 depending on use, storage and event programme
Fuel economy
10–18 mpg typical; heavy carburetted engines run rich
Insurance
Use a specialist agreed-value vintage policy with declared value reviewed annually. Premiums reflect declared value, storage, event use and driver experience with pre-war machinery.

Maintenance planning

Vintage cars require disciplined preventive maintenance: lubrication regimes, magneto service, carburettor synchronisation, brake adjustment, and timber and trim conservation. A car used regularly and serviced annually by a specialist will outlast a stored example neglected for decades.

Specialist access and parts

Strong US ACD Club support; specialist mechanical and coachwork shops in the Midwest and elsewhere. Confirm the availability of marque specialists, period-correct fasteners, coachwork trim, instruments and tyres before committing. A car requiring fabricated one-off parts will absorb time and cost that a similar example with active specialist support will not.
Common Problems

Known issues by system

Engine

Lycoming DOHC straight-eight valve gear wear

Major$15,000 – $40,000
Symptoms — Top-end clatter, valve adjustment drift, reduced compression.
Inspection — Compression test all 8; inspect valve gear; verify ACD Club specialist service history.
Supercharger

SJ centrifugal supercharger bearing wear

Major$20,000 – $50,000
Symptoms — Loss of boost, whine becoming rumble, oil at supercharger.
Inspection — Boost pressure test; remove for bearing inspection; only 36 factory SJs built.
Identity

J vs. SJ vs. JN authentication; re-bodies common

CriticalValue impact: 30–70%
Symptoms — Many Js have been re-bodied or modified to tribute SJ spec.
Inspection — Verify with Auburn Cord Duesenberg Club and known engine/chassis records.
Coachwork

Murphy / Derham / LeBaron / Rollston / Bohman & Schwartz body originality

CriticalValue impact: 40–60%
Symptoms — Coachwork is the value driver; verify body number stampings.
Inspection — ACD Club and coachbuilder archive review; period photographs essential.
Auctions

Recent results

DateAuctionCarMileageResult
2026-03-06
Broad Arrow Auctions
The Amelia Auction, Lot 275
1935 Model J Supercharged
$1,655,000
Sold
2025-08-15
RM Sotheby's
Monterey, Lot 157
1935 Model J Torpedo Phaeton
$4,405,000
Sold
2024-08-16
Gooding Christie's
Pebble Beach Auctions, Lot 25
1934 Model J Disappearing-Top Convertible Coupé
$3,745,000
Sold
2023-08-17
RM Sotheby's
Monterey, Lot 352
1935 Model SJ 'Sweep Panel' Dual-Cowl Phaeton
$3,030,000
Sold
Investment

Long-term outlook

Blue ChipHorizon: 10+ years

America's grandest pre-war car. ACD Category 1 SJs are essentially blue-chip globally.

Our view, not advice. This section is Car Collector International's editorial judgement on where this model sits in the collector market, based on the production, specification and market data set out in this guide. It is not a recommendation to buy or sell and it is not investment advice. Values can fall as well as rise.

Recommended

The trusted network

Specialists

  • Duesenberg marque specialist
    View →
    UK / Europe
    Duesenberg Model J / SJ restoration, mechanical service and originality reviews.
  • Pre-war coachwork specialist
    View →
    International
    Timber framing, ash conservation, panel beating and period-correct paint for pre-war coachwork.
  • Concours preparation studio
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    International
    Concours preparation, detailing and event support for pre-war and vintage cars.
  • Hagerty
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    USA / UK / EU
    Agreed-value collector insurance specialising in pre-war and vintage cars.
  • Lockton Performance
    View →
    UK / EU
    Specialist agreed-value cover for significant pre-war and competition cars.

Storage

  • Windrush Car Storage
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    London & Cotswolds, UK
    Climate-controlled storage and collection management for pre-war and classic cars.
  • AutoVault
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    Essex, UK
    Dehumidified storage at 55% RH in purpose-built sealed buildings, with maintenance programmes and individual motor-trade insurance cover.
  • Classic Car Club Manhattan
    View →
    New York, NY
    Secure urban storage for collector and pre-war cars.

Transport

  • CARS UK
    View →
    UK & Europe
    Enclosed concours and event transport for pre-war and vintage machinery.
  • Reliable Carriers
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    USA (national)
    Enclosed coast-to-coast transport for pre-war American and European cars.
  • FERRLOG
    View →
    Italy / Europe
    Air-ride enclosed transport for Italian and European collector cars.

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The valuation figures in this guide are for research purposes only and do not constitute financial or investment advice. See our full disclaimer.