Half a century after its introduction, the 123 series remains synonymous with the absolute pinnacle of German engineering and quality.
In 1976, Mercedes-Benz introduced the 200-300 class, known internally as the W123, which is now considered a true masterpiece in terms of reliability and technical perfection. Development began as early as 1970, with the designers relying heavily on the technology of the then S-Class. In order to ensure absolute top-quality series production and not to disrupt regular production, the brand invested around 10,2 million euros in a special pilot plant. There, assembly processes were thoroughly optimised and errors were eliminated before the car reached the general public, laying a solid foundation for its later legendary reliability.
The international automotive press welcomed the new Mercedes with praise for its superb build quality, revolutionary safety and comfort, although journalists criticised the high price and rather modest standard equipment. Competitors such as the more dynamic BMW 5 Series and the cheaper six-cylinder models from Ford and Opel offered different advantages, while the Japanese brands fitted luxuries as standard, for which one had to pay a significant extra in Stuttgart. Although many pointed out that the basic diesel model 200D with its 40 kW (55 hp) was desperately slow, the thoughtfully designed and high-quality construction of the whole package won. The 280E was even named Import Car of the Year in the USA.
Underneath the seemingly conservative and timeless design, which was deliberately designed to defy fashion fads and later also ensure the high value of the used car, were revolutionary safety innovations for the time. The W123 was equipped with extensive crumple zones, a greatly improved passenger safety cage, and the fuel tank was moved from the bottom of the trunk to a more secure location above the rear axle. Even the spare wheel became part of the comprehensive safety concept to mitigate rear impacts. In its later years, the W123 also brought advanced technologies such as ABS and airbags, which had previously been reserved only for the most prestigious sedans, to a wider range of customers.
At launch, Mercedes offered the classic four-door W123 sedan, but the series was quickly expanded with the elegant C123 coupe, extended versions for taxis and ambulances, and the extremely popular S123 station wagon (Model T). Global demand immediately reached such proportions that buyers – especially for the highly sought-after diesel models – had to wait up to two years for their car. The shortage of these cars even led to the emergence of a lively black market in Germany, where a signed purchase contract with an early delivery date could be resold for a premium of more than 2.500 euros.
In terms of engines, a tried-and-tested range of petrol and diesel engines was initially available, culminating in 1980 with the 92 kW (125 hp) turbodiesel in the 300D. The absolute top petrol engine was the 280E, whose six-cylinder engine initially developed 130 kW (177 hp), but was upgraded to 136 kW (185 hp) after 1978. The engineers also used the 123 series as a testing ground for alternative powertrains; they experimented with hydrogen, methanol and even built a test wagon with a 30 kW (41 hp) electric motor and a 600 kilogram battery pack. For collectors and purists, the holy grail today is the richly equipped 280 TE wagon with a five-speed manual transmission, produced after 1982.
The historical significance of the W123 model can hardly be overstated today. With a total of 2,7 million units produced, this exceptional sales success provided Mercedes with the financial backing to develop the more complex 190 series and the W124 model. The car embodies the absolute pinnacle of German engineering perfectionism and set standards of durability that the brand had difficulty achieving in later decades (mainly due to problems with rust and electronics). The fact that the 123 series proved to be virtually indestructible is also confirmed by the number of surviving vehicles around the world. In many places, these models are still used as daily taxis.
