The world premiere of the SEC Coupés from the C 140 series was staged at the North American International Auto Show in Detroit in January 1992; the European premiere followed two months later at the Geneva Motor Show.

The brochure of 1992 had this to say: “The new SEC Coupés are under the obligation of continuing a long-standing and successful tradition – a tradition of exclusiveness which is based on rarity and an out-of-the-ordinary character of form. The Mercedes-Benz Coupés have been writing design history since the end of the 1920s.”

Initially two versions were offered: the 500 SEC with a V8 engine (235 kW) and the 600 SEC with a V12 engine (290 kW). Their engines and most of the engineering were identical with the corresponding Saloons from the 140 series. Both were the top-of-the-range models from Mercedes-Benz – supplied with numerous extras ex factory. In stylistic terms, however, they were clearly more independent than their predecessors from the C 126 series. “With the renunciation of everything superfluous, and with its clean, smooth lines, the S-Class Coupé proves that dynamism can do without ostentatious sportiness,” the brochure from the year 1993 said.

New model designations for all model series
Analogous to the other passenger car models from Mercedes-Benz, new model designations were introduced for the large Coupés in June 1993 as well, and the 600 SEC, for instance, was renamed S 600 Coupé. From then on, the model plate on the trunk lid only revealed the displacement and the class of car, but no longer the type of bodywork – which was obvious anyway.

At the Geneva Motor Show in March 1994, two years after their European premiere, the Coupé family was extended by the addition of the S 420 Coupé which served as a more favourably priced entry-level model and, like its four-door counterpart from the Saloon series, was powered by a 4.2-litre four-valve V8 engine which developed 205 kW.

Two major technical innovations were available in the S 600 Coupé for the first time: in May 1995, a completely newly developed five-speed automatic transmission with slip-controlled torque converter lock-up clutch and electronic control was introduced which went a long way towards reducing fuel consumption. Improvements were also achieved with respect to weight and dimensions in that the new automatic transmission was clearly lighter and more compact than comparable transmissions with five gear stages and could also be produced more economically as the number of individual components was reduced by almost 40 percent. Another innovation of even greater significance was introduced at the same time: the Electronic Stability Program ESP® which supports the driver in the case of driving faults in that it counteracts instability through selective brake intervention, controlled by sensors, and thus contributes to safety.
From September 1995, the electronically controlled automatic transmission was also installed in the eight-cylinder Coupés; at the same time, the ESP® became optionally available for both models.

In June 1996, the model designations of the Coupés were changed again. The series was now called CL – and this was no end in itself but was to indicate that the large Coupés adopted a pacemaker function for the entire Coupé family. At the same time, the CL Coupés also presented themselves in stylistically discreetly modified form: the externally distinguishing features were the revised bumpers with integrated sensors for the PARKTRONIC ultrasonic parking aid which was included in the standard specifications and replaced the previous guide rods on the rear fenders. Other remarkable innovations were xenon headlamps with dynamic headlamp range adjustment, Tempomat cruise control operating down to 30 km/h, side airbags as standard and a seat occupancy recognition sensor for the front passenger’s seat.

Matured in this way, production of the CL models was discontinued in September 1998, almost precisely six years after the start of series production. Overall, 26,022 Coupés from the C 140 series had been built at the Sindelfingen plant.

The 140 series in the press
Auto, Motor und Sport, issue no. 3/1993, after a test comparing the Mercedes-Benz
600 SEC with the BMW 850 CSi and the Jaguar XJR-S: “The Mercedes may not be the king of the road but is the uncontested master in terms of ride comfort. Optimum levels of noise suppression, seat comfort and climate control add up to a standard of comfort which is far above that of the two twelve-cylinder competitors.”

Frankfurter Allgemeine Zeitung, Germany, 16 March 1993, on the Mercedes-Benz
600 SEC: “It is hard to imagine a quieter ride, even at high speed the wind merely whistles a quiet tune. Forceful acceleration is required if you want to hear the engine – and with such regal power at one’s disposal that occurs when most others have already given up.”

Road & Track, USA, April 1993, on the Mercedes-Benz 600 SEC: “Fit for a king (and fetching a princely sum), this S-Class Coupé is just what someone like, say, Ludwig II would drive, were he alive today. You see, the 600 SEC is a Mad King kind of automobile, a mechanical metaphor for Ludwig’s castles, Neuschwanstein, Linderhof and Herrenchiemsee. Now it would be a cheap shot to suggest that this Merc is as large as a palace, so let’s just say it’s as opulent, as distinctively styled, as inventively engineered and as comfortable as one of Ludwig’s edifices. And, unlike a castle, the 600 SEC is mobile – and fast.”

Source: Daimler AG