Since their first appearance in 1996, the compact SLK Roadsters have come to symbolise Mercedes-Benz’ dynamic brand image. Already a familiar sight on our roads, the second-generation two-seater is to be further enhanced with the implementation of a raft of measures in 2008, the aim being to further emphasise the car’s sporty character and continue the SLK-Class success story by introducing new, dynamic, powerful elements. Some 310,000 first-generation roadster models were sold between 1996 and 2004. And around 185,000 customers – some 60,000 of them in Germanyalone – have already purchased the second-generation model since its launch in March 2004 (figures at year-end 2007). This means that total unit sales of the SLK Roadster are now approaching the half-million mark.
The new-generation SLK displays new sporty highlights, further enhancing the appeal of the successful two-seater with the trendsetting vario-roof that transforms the car from a roadster into a weatherproof coupé in a matter of seconds.
Distinctive character: even more pronounced arrow shape at the front end and a diffuser-style rear end
The designers have given the already dynamic-looking two-seater cult model an even sportier appearance. Eye-catching features include the new-look front bumper with a modified air-dam arrangement and a more pronounced arrow shape. Plus the area around the Mercedes star has been restyled to render it even more succinct. In addition, the designers have modified the rear end by introducing a diffuser-style lower section that makes the Roadster appear more powerful when viewed from behind – an effect that is enhanced considerably by the trapezoidal exhaust tailpipes and the AMG-inspired darkened tail lights. The now larger exterior mirrors feature LED indicators with a pronounced arrow shape, while the range of light-alloy wheels is also almost entirely new.
High-quality cockpit and new three-spoke sports steering wheel
Many of the interior details have also been redesigned and upgraded following a careful process of material selection. Particular importance was attached to optimising the interior so as to make it even more driver-oriented. Centrepieces include a new three-spoke sports steering wheel with multifunction buttons and a new instrument cluster with captivating dial surrounds.
New “gullwing red” leather appointments will be available – reminiscent of the interior appointments in the legendary 300 SL gullwing model. Further new additions include nappa leather appointments in “natural beige”, which complement the new “pale burr walnut” and “black ash grain” wood trims perfectly.
Enhanced audio and telematics systems
Mercedes-Benz is installing the new NTG 2.5 audio and telematics generation in the SLK for the first time. It is easier to operate and offers an even wider range of useful functions. Standard features integrated in every radio include a hands-free system with Bluetooth technology and a new media interface in the glove compartment, allowing the full integration of mobile audio devices such as an iPod, which can then be operated via the audio system’s user interface.
Together with the new telematics generation, Mercedes-Benz is also offering the LINGUATRONIC voice-operated control system as an optional extra in the SLK-Class for the first time.
Voluminous surround sound even when the roof is open
Passengers can enjoy a unique listening experience, regardless of whether the vario-roof is open or closed, thanks to the optionally available harman kardon® Logic7® sound system. Rich and voluminous surround sound makes for crystal-clear listening pleasure, the like of which has never before been associated with a roadster.
Fast-running sports engine: higher output and much lower fuel consumption
The sporty credentials of the 2008 SLK generation are further enhanced by three modified powerplants that consume less fuel and, therefore, emit less CO2. The four-cylinder powerplant in the SLK 200 Kompressor and the six-cylinder sports engine in the SLK 350 both offer substantially more power and torque. Only the SLK 55 AMG retains its familiar engine – an eight-cylinder unit that has lost none of its mesmerising performance capability and remains a unique selling point in the SLK segment.
The Mercedes-Benz engineers paid special attention to the fast-running V6 sports engine that makes its debut in the new-generation SLK, totally altering the six-cylinder unit’s character by making sweeping changes to the mechanical setup. Although the displacement remains the same at 3498 cc, the engine now develops 224 kW/305 hp at 6500 rpm – some 24 kW (33 hp) more than its predecessor. The peak torque has also been boosted, by 10 Nm, and now stands at 360 Nm when the engine is running at 4900 rpm.
This result was achieved by raising the engine speed limit to 6800 rpm; it can even be increased to 7200 rpm for a brief period – oil temperature and other engine parameters permitting. Other changes introduced include a higher compression ratio, a new intake manifold and an extensively modified valve train.
Further aspects which add to the emotionally charged appeal of the new engine include deliberately powerful sports-engine acoustics with a strikingly emotive sound design when decelerating. In combination with the 7G‑TRONIC automatic transmission, the engine management system also blips the throttle automatically during downshifts. As well as producing an extremely sporty sound, this throttle-blipping function reduces load alteration effects.
Despite the higher output and high-calibre performance, the SLK 350 consumes considerably less fuel. With the six-speed manual transmission on board, combined fuel consumption is just 9.5 litres per 100 km, a remarkable reduction of 1.1 litres per 100 km; if the 7G-TRONIC automatic transmission is fitted, the sports powerplant returns a combined fuel consumption of just 9.2 litres per 100 km – an improvement of 0.9 litres compared to its predecessor. Lower fuel consumption means that CO2 emissions are also reduced – by 23 g/km to 219 g/km in the automatic version and by 28 g/km to 227 g/km in the manual version.
Three further engines to choose from
The engine line-up for the second generation of the successful SLK-Class is being augmented by three further variants: The output of the four-cylinder supercharged engine has been boosted by 15 kW/21 hp (to 135 kW/184 hp), while its torque has been increased from 240 to 250 Nm. Combined fuel consumption has been cut by 1.0 litres to 7.7 litres per 100 km whilst CO2 emissions have been reduced by 27 g/km to 182 g/km.
The SLK 280 has also been further improved with respect to fuel economy and, therefore, CO2 emissions. Fuel consumption has been cut by 0.4 litres to 9.3 litres per 100 km (if an automatic transmission is fitted, the figure is 0.2 litres lower at 9.1 litres per 100 km), while CO2 emissions have been reduced by 11 g to 220 g/km (if an automatic transmission is fitted, the figure is 6 g lower at 216 g/km). The SLK 55 AMG is still equipped with the familiar 5.5-litre V8 powerplant developing 265 kW/360 hp and a peak torque of 510 Nm.
Standard equipment for the three new SLK models includes a precise six-speed manual gearshift, while the SLK 55 AMG still comes with the 7G‑TRONIC Sport seven-speed automatic transmission fitted as standard. Optional extras available include a five-speed automatic transmission for the SLK 200 and the 7G-TRONIC seven-speed automatic transmission or, alternatively, the 7G-TRONIC Sport with shift paddles on the steering wheel for the six-cylinder SLK 280 and SLK 350 models.
New direct-steer system for outstanding agility and tangible driving pleasure
A newly developed direct steering system with variable steering assistance, available as an optional extra (standard for the SLK 55 AMG), further highlights the qualities of the sporty chassis, combining agility and manoeuvrability when driving on twisting rural roads with steering comfort when parking and assured steering characteristics when travelling at high speed.
The direct- steer system is based on the previously installed speed-sensitive power steering system and operates by purely mechanical means, meaning that there is no need for elaborate actuators and complex sensors. At its heart is a new rack with slick gearing, which ensures that the steering gear ratio changes in tune with the steering angle. The ratio is indirect when the steering is in or around the central position so as to ensure excellent straight-line stability and, therefore, a high degree of assuredness when travelling at high speed. At a steering angle of just 5 degrees, the ratio starts to increase extremely rapidly and the steering feels much more direct. As a result, the number of steering wheel revolutions from lock to lock is reduced by around 25 percent if the new direct steering is fitted. This means that, even in city traffic, relatively little steering wheel movement is required to correct the car’s path. Fast sequences of bends on rural roads can be negotiated almost intuitively with relatively small steering movements – with assurance, precision and a healthy dose of driving enjoyment.
Visually enhanced SLK 55 AMG
On a technical level, the SLK 55 AMG remains almost unchanged. The only differences are a few visual enhancements. The front end of the AMG model now features a new apron with a black-painted cross strut and side air outlets as well as darkened headlamps.
The trendsetting SLK
As trendsetters and technology leaders, the SLK-Class Roadsters have long enjoyed the image of a modern cult car. Even after the extensive modifications, the familiar outstanding qualities remain, for example, the vario-roof that transforms the roadster into a coupé in 22 seconds, not to mention the extensive standard-equipment package, including head/thorax sidebags, adaptive front airbags and two-stage belt-force limiters. Plus the roadster also comes with the option of the unique AIRSCARF neck-level heating system, which allows open-top driving pleasure all year round, even in winter.