The S-Series grew from the Mercedes-Benz Model K, itself a race-oriented short-wheelbase variant of Daimler's pre-merger Type 630 luxury car. Following the 1926 amalgamation of Daimler and Benz & Cie into Daimler-Benz, the new corporation resolved to build a more advanced competition car on the best features of the Model K. The engine's design code was M06, with the vehicle carrying the designation W06, following the post-merger convention of using M for motor and W for Wagen.
The foundation of the series was the Model S. The six-cylinder engine from the Type 630 was enlarged by widening the bore 4 mm to increase displacement from 6.3 litres to 6.7 litres. The chassis retained the Model K's dimensions but was lowered significantly, and the engine was moved 30 cm rearward. This combination improved weight distribution, lowered the centre of gravity, and substantially enhanced handling. With the supercharger engaged, the M06 engine produced 180 hp.
In mid-1928 Daimler-Benz introduced the SS, standing for Super Sport. Intended as a grand tourer, it used a wet cylinder liner arrangement that allowed the M06 to be bored out further, raising displacement to 7.1 litres and output to 200 hp with the supercharger. The SS could achieve a top speed of 118 mph, two to three times the capability of most road cars of its era.
The S and SS were formidable on open circuits but less suited to hillclimbs and tighter events where agility mattered. Late in 1928 Daimler-Benz introduced the SSK — Super Sport Kurz, meaning Super Sport Short — with a wheelbase shortened to 2,950 mm. The SSK used the improved SS engine but retained the lower radiator of the base S model. Its improved handling and 119 mph top speed made it highly competitive in sprints, hillclimbs, and shorter road races.
The SSK was the last car designed for Mercedes-Benz by Ferdinand Porsche before he departed to establish his own company.
In 1931, with the SSK established as both a competition success and a commercial product sold to wealthy customers, Daimler-Benz produced a limited run of a pure racing derivative not available through ordinary sales channels. The SSKL — Super Sport Kurz Leicht, meaning Super Sport Short Light — reduced the SSK's weight by 125 kg through extensive perforation of the frame members. Combined with a power output of 300 hp, the SSKL achieved a top speed of 146 mph.
Of particular note was the SSKL campaigned by Manfred von Brauchitsch, which was fitted with a streamlined aluminium body. This car reached 156 mph and won at the Avus race in May 1932. Radio commentators covering the event referred to the aluminium-bodied car as a "silver arrow" — a term that would become synonymous with Mercedes-Benz racing cars of the following decade.
Daimler-Benz concluded that combining a road car and a racing car in a single platform was no longer a viable approach as the 1930s progressed. The S-Series was succeeded by two separate lines: the 500K, a mass-produced sporting luxury car for wealthy road users, and an entirely new generation of purpose-built racing cars that carried the silver arrows name into the 1934 Grand Prix season.
The S-Series represented a transitional moment in European motorsport, bridging the touring-car competition of the 1920s and the purpose-built Grand Prix machinery of the 1930s. The SSKL in particular demonstrated that aerodynamic thinking could meaningfully alter the competitive calculus of a racing car, anticipating preoccupations that would define the Silver Arrows era. The S/SS/SSK line was among the nominees in the penultimate round of voting for the Car of the Century award in 1999.