Manufacturer Daimler-Benz Layout FR layout | Production 1996–present | |
 | ||
Class Sport compact / Roadster Body style 2-door coupé2-door roadster | ||
The Mercedes-Benz SLK-Class is a compact luxury roadster manufactured by Daimler-Benz in three generations; R170 launched in 1996, the R171 in 2004 and R172 in 2011.
Contents
- Concept history
- R170 19962004
- Roof mechanism
- R170 facelift 2000
- R170 range summary
- The SLK in the USA
- R171 20042010
- R171 facelift 2007
- R172 2011Present
- R172 range
- References
Mercedes presented the SLK II concept car at the 1994 Paris Motor Show, showing off the "vario-roof". The car went on sale two years later in Europe, and in 1997 in the US. The SLK is built in Bremen, Germany.
The designation "SLK" derives from the company's design mission to create a roadster that was at once sporty, light and short—in German: sportlich (sporty), leicht (light) und kurz (short).
For the 2017 model year (late 2016), with the release of the third generation R172 facelift, the SLK-Class will be renamed to Mercedes-Benz SLC-Class in accordance with the revised nomenclature adopted by the brand. Under this scheme, roadsters use the base name "SL", followed by the model's placement in Mercedes-Benz hierarchy. The "SL" is for Sportlich Leicht (German for "Sport Light") and alludes to the long-running SL-Class. This is followed by the letter "C"—the SLC being the roadster equivalent to the C-Class.
Concept history
Daimler-Benz wanted to market a new retractable hardtop system they called the "Vario-Roof". first shown on the SLK II concept car at the 1994 Paris Motor Show. The car went on sale two years later in Europe, and in 1997 in the US. The Vario-Roof is a hard roof that can fold down into the car by means of an electrohydraulic system, thus transforming the car from coupé to cabriolet.
As one of the first modern retractable hardtop convertibles, the SLK joined others of this era including the 1995 Mitsubishi 3000GT Spyder, the Peugeot 306 Cabriolet, the Lexus SC, the Pontiac G6, and the Chrysler Sebring.
R170 (1996–2004)
At start of the 1990s, after the introduction of their two-seater grand-tourer R129 SL and the Mazda MX-5, Daimler-Benz set out to create a new compact roadster, positioned below the SL. By late 1991 under Bruno Sacco, the first design sketches were drawn and twelve 1:5 scale models being built in the first half of 1992. By the middle of the year, five of them were proposed again in full-scale. In early 1993, the final design was selected and approved by the board, with the German design patent being filed on September 30, 1993. On April 22, 1996, the new production SLK-Class, based on the R170 platform was introduced at the Turin Motor Show. SLK 230 Kompressor launch model became a competitor to the Porsche Boxster and BMW Z3. It was powered by a 193 hp 2.3 L supercharged straight-4 engine and a choice of automatic transmission or 5-speed manual transmission. The SLK was a modern incarnation of the 1950s Mercedes-Benz 190SL by returning to four cylinders and a 94-inch (2,400 mm) wheelbase. Worldwide sales hit 55,000, over double the entire nine-year production of 190SLs, and between 1996 and 2004, over 311,000 SLKs were sold. The very first U.S.-market R170 Mercedes SLK was completed on November 1, 1996 and went on sale in January 1997 for the 1998 model year. The last was completed on April 7, 2004.
Roof mechanism
The roof design, marketed as the Vario-Roof, consists of a folding steel hard top divided in half along a transverse axis. Both halves are linked by a kinematic mechanism which is locked securely when the roof is closed. At the touch of a button on the centre console, a hydraulic system with five cylinders controls the fully automatic folding process in which the boot lid is also integrated. It opens by tipping to the rear so that the two roof halves have sufficient movement to pivot backwards as the roof opens; the roof sections then position themselves on top of each other and fold into the boot. If the roof is to be closed, the same sequence of movements is performed in reverse order. The hydraulic system stows the roof in the upper section of the boot. A plastic roller blind separates the roof from the luggage space below, a volume with a capacity of 145 litres in the first-generation SLK. With the roof closed, the load volume increased to 348 litres (12.3 cu ft). Two fixed roll-over bars behind the seats worked with the A-pillars to form an integrated system offering a high degree of roll-over protection.
The steel roof provides added protection, which is normally found in a coupe, but with the flexibility of a convertible at the same time.
R170 facelift (2000)
In 1997, development on updates to the R170 began and by early 1998, design work on an updated SLK was completed and patented on February 2, 1998. In February 2000, the SLK received a facelift which included new front and rear bumper designs, body-coloured side skirts and the introduction of new wing mirrors incorporating indicators. The range was expanded to include a new entry-level model SLK 200 Kompressor and a new V6 in the SLK 320 with M112 E32 engine. Technical improvements included the addition of Electronic Stability Program (ESP) and a new 6-speed manual transmission. A stabilizer bar was added to the rear and the front one was reinforced. A 3.46:1 axle was added for the manual shift SLK, and the fuel tank grew from 12 to 14 gallons.
In 2001 a new AMG model was added, with a 349 hp (260 kW) supercharged version of the 3.2 L V6. This SLK 32 AMG was the most powerful R170 SLK, and was a direct rival of the BMW M Roadster and Porsche Boxster S. It was only offered with the newly engineered five-gear "SpeedShift" and boasted 35% quicker automatic shifts. All engines were hand built by AMG by an individual engineer. The SLK32 AMG's engine has two spark plugs per cylinder for maximum combustion and was fitted with an intercooled Lysholm-type twin-screw supercharger. Brakes became 13.15 in (334 mm) diameter, upgraded from the standard 11.8 in (300 mm) items. AMG production ran between Aug 2000 and March 2004. Only 4,333 were built in total, of which 979 were retained for Germany, 2,056 exported to the USA, and 263 to the UK.
In July 2004 a special edition was launched prior to the replacement with the new R171 SLK in 2005. The R170 lived on as the Chrysler Crossfire until 2008, sharing substantial elements of the SLK including engines and interiors.
R170 range summary
Not all models were exported to all markets.
The SLK in the USA
The SLK was announced to the USA market on Sept. 7, 1997 as a 1998 model. The SLK was on Car and Driver's Ten Best list for 1997 and was named “North American Car of the Year” by CAR & DRIVER magazine for 1998. Sales of the SL320 (6 cylinder) were halted in the US when the SLK arrived in order to distance it from the larger SL.
R171 (2004–2010)
The R171 features a number of revisions compared to its predecessor, the R170: a 30mm longer wheelbase, increased length (72mm) and width (65mm), 40% increased use of high strength steel, seven-speed automatic transmission, adaptive two-stage airbags, head/thorax sidebags and a revised roof mechanism (marketed as the Vario roof) deployable in 22 seconds (previously 25 seconds) with a rotary-pivoting rear window enabling a more compact folded roof stack and trunk storage increased by 63 litres with the roof retracted. Optional features include remote operation of the retractable hardtop as well as a forced air, neck-level heating system integral to the headrests, marketed as Airscarf.
The fully galvanized bodywork, which features 19 percent improvement in static bending and 46 percent improvement in torsional strength with the roof down, also features a 3% improvement in aerodynamic efficiency, with a Cd value of 0.32. The design has been aerodynamically optimized to minimize interior draughts with the top retracted and includes a fabric windblocker which can be pulled up over the two roll-over bars. Mercedes marketed the R171's tapering front end styling by designer Steve Mattin as "Formula One-inspired".
Models of this SLK include:
R171 facelift (2007)
In January 2008 at the Detroit Motor Show, the SLK-Class facelift was launched, following pre-show announcements in December 2007 with the first American owner being James Glass of Johnson City TN. The R171 facelift included new engines, with a particular improvement to the SLK 200 and 350 with more power and better fuel efficiency. The exterior changes were subtle, with alterations limited to the front bumper design and new wing mirrors.
R172 (2011–Present)
Development on the R172 began in 2005, with the final design being selected in 2008. Mercedes-Benz announced the new SLK in the autumn of 2010, allowing car magazines to drive disguised test cars several months prior to official announcement in January 2011 and formal public launch at the Geneva Motor Show in March 2011. The company took the unusual step of issuing several press releases in October and November 2010 announcing new features such as "Magic Sky Control".
R172 range
In December 2015 Mercedes presented to the press the new version named SLC-Class, announcing a March 2016 launch date to coincide with the 20th anniversary of the original SLK.
All versions have as standard the 9G Tronic automatic gearbox, except for the 180 and 200 in which a manual 6-speed gearbox is standard, although the automatic is available in option