America's grandest pre-war motor car — 6.9-litre DOHC straight-eight, supercharged SJ, and the most theatrical coachwork in the world.
.jpg?width=1600)
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.
| Variant | Years | Production | Notes |
|---|---|---|---|
| Model J | 1928–1937 | 445 | Naturally aspirated DOHC straight-eight. |
| Model SJ | 1932–1937 | 36 | Roots-supercharged; 320 bhp. |
| Model SSJ | 1935 | 2 | Short-chassis Roadster; Clark Gable / Gary Cooper. |
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.
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.
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.
SSJ short-chassis Roadsters and original SJ supercharged cars lead by an enormous margin; Murphy-bodied convertibles and Bohman & Schwartz Speedsters follow. For vintage cars, event eligibility — Mille Miglia, Goodwood Revival, Pebble Beach, VSCC events, Le Mans Classic — can underwrite a substantial proportion of market value. Verify FIA/FIVA papers, period race history where claimed, and the car's standing with the relevant marque registry before purchase.
Regional ranges authored independently — each reflects its local market, not an FX conversion
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.
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.
Each region quoted in its local currency — independent market readings, not FX conversions
SJ and SSJ leaders firm; mid-tier Murphy convertibles firm; closed coachwork softened modestly.
| Date | Auction | Car | Mileage | Result |
|---|---|---|---|---|
| 2018-08-25 | Gooding & Co. Pebble Beach | 1935 SSJ Roadster (Gary Cooper) | — | $22,000,000 Sold |
America's grandest pre-war car. ACD Category 1 SJs are essentially blue-chip globally.
Join Car Collector International's owners register for valuation updates, auction alerts and members-only events.
Register interestThe valuation figures in this guide are for research purposes only and do not constitute financial or investment advice. See our full disclaimer.
