About 45 years of dust coats this ultra-rare Mercedes-Benz 300 SL ‘Alloy’ Gullwing – one of only 29 ever built. The car belonged to auto collector Rudi Klein and was secretly stored in his junkyard since 1977, eventually forgotten.

Beneath the grime lies an exciting renovation project, with the car expected to fetch up to $6 million when it goes to auction via RM Sotheby’s. The Gullwing was originally commissioned by Ferrari importer Luigi Chinetti and features a lightweight aluminium body, approximately 209 lbs lighter than the steel version. It was equipped with a 3.0-litre straight-six engine that produced 215 hp, along with high-performance sports suspension and ventilated drum brakes—an enticing proposition for amateur racers.

With only 29 ever built, the ‘Alloy’ Gullwing is one of the rarest Mercedes models, iconic for its elegant ‘gullwing’ doors. Klein acquired the car in 1976, stashing it alongside his collection of rare Lamborghinis, Porsches, Ferraris, and Mercedes-Benzes until his death in 2001.

Despite its lofty estimate, the car requires a complete renovation.

Some parts sold were off over the decades, including the front bumpers, shift knob, tool kit, jack, and spare wheel. Nevertheless, it remains remarkably genuine, with the original, matching-numbers engine, gearbox, rear axle, steering box, and front spindles; four road wheels, all with matching date codes; and its factory alloy bodywork. Extremely few of these racing competition cars have survived quite so intact.

More than 20 years after Klein’s death, his sons are finally parting ways with his collection as the Gullwing and others go under the hammer at RM Sotheby’s auction, The Junkyard: The Rudi Klein Collection, on 26 October 2024.

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