The 1953 launch of the Mercedes-Benz 180 (W 120), affectionately known as the “Ponton Mercedes” or “Roundie”, marked a pivotal moment in Mercedes-Benz passenger car history. This intermediate saloon was groundbreaking as the first Mercedes-Benz to adopt both a unibody construction and the distinctive pontoon styling. Serving as a trendsetting ancestor to the modern E-Class, the Mercedes-Benz 180 also profoundly influenced the design and engineering of subsequent luxury models (series 180/105/128 from 1954 onwards). Even at its 1953 unveiling, the Mercedes-Benz 180 immediately captivated industry experts and the public alike with its fresh and modern aesthetic.
The Mercedes-Benz 180, as the new premium intermediate model, distinguished itself from its predecessors with enhanced chrome detailing and larger rear lights.
This “three-box design,” characterized by its rectangular form, integrated fenders, and clearly defined engine, passenger, and boot compartments, established new standards for contemporary automotive design. The Mercedes-Benz 180’s bodywork was a stark departure from Mercedes-Benz’s post-World War II offerings, which still largely echoed design and technical principles from the 1930s. In contrast, the pontoon style, originating in North America in the late 1940s and innovatively reinterpreted by Mercedes-Benz for its intermediate saloons, appeared modern and streamlined. This design evolution significantly reduced the aerodynamic drag of the Mercedes-Benz 180 compared to older models, minimized wind noise, and created a more spacious interior.
Unibody Construction: A Mercedes-Benz First
Technically, the Mercedes-Benz 180’s body was equally pioneering. It was the first Mercedes-Benz passenger car to feature a unibody structure, where the body was firmly welded to the frame floor, forming a single, rigid structural unit. Compared to traditional body-on-frame construction, this approach enhanced torsional stiffness while simultaneously reducing weight. Another innovation was the implementation of double wishbone front suspension, mounted to a front axle carrier instead of directly to the frame.
This U-shaped axle carrier also housed the engine, transmission, and steering components. It was attached to the front frame section using silent blocks to minimize noise and vibration. The rear wheels, utilizing the proven swing axle, were now further controlled by widely spaced trailing arms. These advancements collectively resulted in handling dynamics that were exceptional for the era. In his 1953 road test for “auto motor und sport” magazine, Werner Oswald praised the Model 180, noting that drivers could immediately explore the limits of the engine and suspension capabilities.
The engine powering the Mercedes-Benz 180 was a side-valve, four-cylinder in-line unit with a 1767 cc displacement, producing 52 hp (38 kW). This enabled the Model 180 to reach a top speed of 126 km/h and accelerate from 0 to 100 km/h in 31 seconds.
Expanding the ‘Ponton’ Family
The Mercedes-Benz 180 quickly evolved into a diverse model range. Perhaps the most iconic variant of the “Ponton Mercedes” was the Mercedes-Benz 190 SL sports car, unveiled in New York in 1954 and entering production in 1955. This roadster, part of the 121 model series, utilized a shortened version of the Model 180’s frame-floor and was equipped with a 105 hp (77 kW), 1897 cc four-cylinder engine.
The diesel variant, the 180 D, debuted in 1954 within the 120 model series’ pontoon body. Subsequently, the petrol-engine Mercedes-Benz 190 (model series 121) arrived in 1956, featuring a 75 hp (55 kW), 1897 cc four-cylinder engine. This new top-tier intermediate model differentiated itself from the 180 models through increased chrome trim and larger taillights. Internally designated the 180 a, the original Model 180 was updated in 1957 and also received a larger 1897 cc engine, though tuned to produce 65 hp (48 kW). In 1958, the Model 190 D further broadened the pontoon saloon family as the second diesel offering in the 120/121 series, employing a 50-hp (37 kW) engine derived from the Model 190.
Setting Benchmarks for Luxury
In 1953, the Mercedes-Benz 180 also established benchmarks for Mercedes-Benz’s new luxury class vehicles launched in 1954. Externally, the 220 and 220 S (W 180), along with the 220 SE (W 128) saloons equipped with inline six-cylinder engines, differed from the W 120 primarily in wheelbase (2.82 meters versus 2.65 meters), a larger passenger cabin, and an extended engine compartment. However, the Model 219 (W 105), introduced in 1956 with a six-cylinder engine, retained the smaller body style.
The Mercedes-Benz 180 made automotive history even before its market introduction. The W 120 holds the distinction of being the first car ever captured in a spy photograph. In 1952, “auto motor und sport” magazine published a clandestine image of the forthcoming Model 180, accompanied by a parody of Goethe’s Erlkönig poem, playfully dubbing the new intermediate saloon “Daimler’s youngest child.” This event is credited with popularizing the German term ‘Erlkönig’ (development mule) to describe pre-production prototypes before their official release.
text – photography/daimler ag
