In December 2007, Mercedes-Benz presented the SLK Roadster of the R 171 model series, which had been updated with around 650 newly developed components. The facelift given to the bestseller brought innovations in both visual and technical terms.
The former included the redesigned front bumper, which formed a striking focal point with a modified layout of the cooling air openings and a more pronounced sweep. The area around the Mercedes star has also been modelled more concisely. The designers paid particular attention to the rear section of the Roadster, where a diffuser look including trapezoidal exhaust trims and AMG-style darkened tail lamps created an updated appearance. The exterior mirrors were designed with LED indicators in an eye-catching arrow shape and now offered more mirror surface.
The interior was also upgraded in many details. A new three-spoke sports steering wheel with multifunction buttons and an equally new instrument cluster were particularly eye-catching. In terms of infotainment, the facelifted SLK Roadster benefited from the first-time use of the latest NTG 2.5 audio and telematics generation, which was characterised by improved user-friendliness and even more useful functions. A hands-free system with Bluetooth technology was now integrated into every radio as standard, and a new media interface housed in the glove compartment was also available on request, via which mobile audio devices such as an iPod were fully integrated. The LINGUATRONIC voice control system, which conveniently activated the telephone, audio and navigation system via verbal full-word input, was now also available as an option.
On the drive side, the revised SLK Roadsters were significantly sharpened in some cases. On the one hand, this applied to the best-selling model, the SLK 200 KOMPRESSOR, whose turbocharged 1.8-litre four-cylinder engine had been given a considerable power boost. Instead of the previous 120 kW/163 hp, the engine now boasted 135 kW/184 hp and an increased maximum torque of 250 Nm. Despite the correspondingly improved driving performance with a top speed of 236 km/h, the average standard fuel consumption of 7.7 to 7.9 litres per 100 km was reduced by around 1 litre compared to the previous model.
At the top end of the model range, the V6 engine of the SLK 350 was also given a significant power boost. From then on, the engine was labelled as a sports engine and now delivered 224 kW/305 hp, 24 kW/33 hp more than before. In addition to the increase in power, the sports engine was characterised in particular by a higher revving capacity, which, with a nominal speed raised to 6500 rpm, brought it close to specially designed high-revving engines. The torque peak of 360 Nm was now only reached at 4900 rpm. Irrespective of this distinctly sporty performance characteristic, the fuel consumption figures were reduced: Depending on the transmission, the SLK 350 sports engine boasted an average standard value of 9.0 to 9.7 litres per 100 km – around 10 % less than the predecessor model.
In contrast, the 3.0-litre V6 engine of the SLK 280, which was positioned in the mid-range segment, presented itself with unchanged performance data and continued to mobilise 170 kW/231 hp. Further refinements in detail, such as the increased compression ratio from 11.1 to 11.3, also ensured reduced fuel consumption and, correspondingly, more favourable emission values. The reductions compared to the previous model were between 2 % and 5 %, depending on the transmission.
The SLK 55 AMG also started its second model cycle with the same engine specifications as before. Under the bonnet was still the beefy, almost 5.5-litre naturally aspirated V8 engine with 265 kW/360 hp and a maximum torque of 510 Nm. Visually, a new front apron with a black-painted cross strut and side air outlets now characterised its face.
In terms of power transmission, the standard 6-speed manual transmission for the SLK 200 KOMPRESSOR, SLK 280 and SLK 350 sports engine models and the AMG SPEEDSHIFT 7G-TRONIC in the SLK 55 AMG, which could also be operated via shift paddles on the steering wheel, were retained after the facelift. As before, a 5-speed automatic transmission was available as an option for the SLK 200 KOMPRESSOR and the 7G-TRONIC for the six-cylinder models, which could also be fitted with steering wheel gearshift paddles on request and in this case was designated 7G-TRONIC Sport.
The qualities of the generally sporty, unchanged specification suspension were now even better emphasised by a newly developed, optionally available Direct-Steer system with variable steering assistance. It combined agility and manoeuvrability on winding country roads with steering comfort when parking and stable steering behaviour at high speeds.
The range of light-alloy wheels was almost completely revised. Only the SLK 200 KOMPRESSOR retained the previous 16-inch rims with 205/55 tyres in the standard version. All six-cylinder models received light-alloy wheels in a new design, the SLK 280 in 16-inch format and the SLK 350 sports engine in 17-inch format, in each case with the previous mixed tyres 205/55 at the front and 225/50 at the rear or 225/45 at the front and 245/40 at the rear. In addition, three new wheel designs – also with mixed tyres – were available as special equipment for all engine versions.
At the time of their respective market launch, the following gross list prices were reported for the updated SLK models: The SLK 200 KOMPRESSOR cost from 36,503.25 euros, the SLK 280 from 41,858.25 euros and the SLK 350 sports engine from 46,975.25 euros. As expected, the high-specification SLK 55 AMG came out on top at 69,049.75 euros.
At the Geneva Motor Show in March 2009, Mercedes-Benz presented the SLK 300 for the first time, which replaced the previous SLK 280 as part of a cross-series adjustment of the model nomenclature. The numerically higher model designation was now in line with the displacement of the 3.0-litre V6 engine; in terms of specifications and performance data, there were no changes to the SLK 300 compared to its predecessor.
Also on show in Geneva was the new, attractive "2LOOK Edition" special model. It was deliberately aimed at a younger target group and played with the visual effects of colour coding in the standard paint colours of calcite white or black. As an option, the SLK 2LOOK Edition was also available in exclusive obsidian black metallic or in the special paint finish designo mystic white, which was limited to 300 vehicles worldwide.
In addition, black-rimmed headlamps and 18-inch 5-twin-spoke light-alloy wheels fitted with 225/40 front and 245/35 rear mixed tyres emphasised the striking appearance of the Edition model. As a special feature – and in keeping with the colour philosophy of the "2LOOK Edition" – the rims were available in two different surface finishes: in shiny titanium silver or alternatively in the darker shade of Chrome Shadow. Further distinguishing features of the special model were the Edition labels on the wings and the standard wind deflector made of transparent acrylic glass, also with the "2LOOK Edition" logo.
The interior of the new SLK 2LOOK Edition was also characterised by black and white
Contrast effects the picture. For example, the sports seats upholstered in nappa leather had white seat centre panels and black seat bolsters. The centre armrest and the multifunction steering wheel, also upholstered in black nappa leather, were finished with white topstitching, and the trim parts in the black instrument panel were also in white. The white-trimmed floor mats had an embroidered Edition label and rounded off the exclusive colour scheme of the special model.
The "2LOOK Edition" equipment package could be combined with all four- and six-cylinder models in the SLK range, but not with the AMG version; it was priced at a linear 2,100.00 euros.
At the beginning of 2010, Mercedes-Benz once again offered a special model of the Roadster series under the name "Grand Edition". As always, it was characterised by useful additional features and a refined exterior and interior. Eye-catchers in the exterior appearance were special 18-inch light-alloy wheels in a 5-triple-spoke design, silver-coloured fins on the bonnet air inlets, dark-rimmed headlamps and the optional designo graphite paint colour. The "Grand Edition" models were available as standard in a choice of black, calcite white or the vibrant red colour fire opal.
In the interior, newly designed seats with two-tone nappa leather upholstery in an exclusive colour mix of basalt grey and designo pearl with contrasting red topstitching set their own accents. This colour scheme was also used for the interior trim, floor mats and trim elements, each in an adapted form. The equipment package for the "Grand Edition" models also included the AIRSCARF® headroom heating system.
Once again, with the exception of the SLK 55 AMG, all engine variants of the SLK were available as the "Grand Edition" special model. This time, however, the corresponding scopes were not summarised in a package price; instead, the respective vehicles were provided with a complete gross list price. The range of Edition versions extended from 42,274.75 euros for the SLK 200 KOMPRESSOR to 51,318.75 euros for the SLK 350, which had since lost the additional designation "Sportmotor" used in the sales documents.
Over its entire production period from 2004 to 2010, a total of around 242,000 vehicles of the SLK Roadster from the R 171 model series were manufactured. For a niche model, this could be considered a complete success, even though around 70,000 more units of the predecessor R 170 series had left the Mercedes-Benz production plant in Bremen. However, it had to be taken into account that the vario-roof pioneer had a total production cycle of ten years instead of six, like the R 171.
Nevertheless, the production statistics after the facelift for the second SLK generation revealed certain weakening tendencies. The reasons for this were manifold and ranged from exogenous factors such as the global financial and economic crisis of 2008/09 to a trend towards smaller target customer groups for vehicles in the segment in question and increased competitive activity.
However, the entry-level SLK 200 KOMPRESSOR remained by far the most popular model during the second production cycle of the 171 model series: A total of almost 33,500 units were built here. Second place in the ranking was taken by the SLK 280, which was renamed the SLK 300 at the beginning of 2009, with over 11,200 vehicles. The most powerful six-cylinder-engined model, the SLK 350 with a re-sharpened sports engine, sold a good 7,100 vehicles. Just under 1,400 units of the AMG model, which was in a significantly higher performance and price range, were built.
The world premiere of the SLK R 172 model series, scheduled for January 2011, proved that those responsible at Daimler AG at the time still considered the market volume for mid-range roadsters to be absorbent and therefore profitable enough to engage in this segment with a comprehensively redeveloped generation of vehicles, despite the changing environment.
