Mercedes-Benz 300 SLR Uhlenhaut Coupe

Mercedes-Benz 300 SLR Uhlenhaut Coupe

The 1954 Mercedes-Benz 300 SLR Uhlenhaut Coupe is arguably the most significant and valuable automobile in existence. Named after Rudolf Uhlenhaut, the chief engineer who conceived it and used one as his personal transport, only two examples were ever built. In 2022, one of these extraordinary machines sold at a private auction for 135 million euros, making it the most expensive car ever sold.

The 300 SLR was not, despite its name, a development of the 300 SL road car. Rather, it was the closed-coupe version of the W196S open sports racing car that dominated the 1955 World Sports Car Championship. The car shared its fundamental architecture with the W196R Formula One car that carried Juan Manuel Fangio to two consecutive world championships in 1954 and 1955.

At its heart was a 2,982cc inline-eight engine featuring desmodromic valve actuation, a system in which the valves were both opened and closed mechanically rather than relying on springs. This allowed the engine to rev safely to extremely high speeds, producing approximately 310 horsepower at 7,500 rpm. The engine was fed by Bosch mechanical fuel injection and breathed through a complex eight-into-four exhaust system.

The space frame chassis was constructed from lightweight magnesium and aluminum alloys, contributing to a total weight of approximately 1,150 kg. The bodywork featured the same gullwing doors as the 300 SL road car but with a more aerodynamically refined shape developed through extensive wind tunnel testing. The body panels were formed from lightweight magnesium alloy.

Suspension was fully independent, with double wishbones and torsion bars at the front and a low-pivot swing axle with torsion bars at the rear. Massive inboard drum brakes were used at the rear to reduce unsprung weight, while the front brakes were conventionally mounted. The overall dynamic package was extraordinarily sophisticated for the mid-1950s.

The Uhlenhaut Coupe was built as a potential entry for the 1956 racing season, but Mercedes-Benz's withdrawal from motorsport following the catastrophic 1955 Le Mans disaster meant the cars never competed. Rudolf Uhlenhaut famously used chassis number 0008/55 as his daily driver, reportedly commuting at speeds that rivaled contemporary racing cars. Colleagues recalled him arriving at the factory having averaged over 100 mph on public roads.

The two Uhlenhaut Coupes remained in Mercedes-Benz's collection for decades. The sale of one in 2022 for 135 million euros to a private collector, facilitated through an exclusive invitation-only auction by RM Sotheby's at the Mercedes-Benz Museum, established a new benchmark for the value of a single automobile. The remaining car continues to reside in the Mercedes-Benz Museum in Stuttgart.

The 300 SLR Uhlenhaut Coupe transcends the category of collector car. It is a cultural artifact representing the absolute zenith of 1950s racing technology, the genius of Rudolf Uhlenhaut, and the dramatic circumstances surrounding Mercedes-Benz's withdrawal from motorsport.