High-quality technology, fascinating styling and driving pleasure for four passengers - these features distinguished the new convertible of the CLK-Class, which Mercedes‑Benz first presented to the public in spring 2003. The Stuttgart-based brand thus continued its successful tradition of open-top, four-seater cars.
Since 1998 the model designation 'CLK' was considered the trademark for convertible pleasure at the highest level. The technical innovations and the attractive design of the new CLK Convertible of the 209 model series provided the optimal basis for drawing on the successes of the predecessor model, which had enthused over 115,000 male and female drivers.
The CLK Convertible attained best values in aerodynamics (coefficient of drag Cd = 0.30), in noise comfort and in boot capacity (390 litres). In the area of occupant safety, the convertible's highly stable body structure, automatic roll-over protection, standard head/thorax side airbags, adaptive airbags for driver and front passenger and emergency belt tensioners at all seats marked additional progress. Equally exemplary was the comfort of the new Mercedes‑Benz Convertible, distinguished in the interior by even more space and by a further expansion of standard equipment.
The newly developed multi-layered fabric top provided optimal noise comfort and operating convenience; it opened and closed fully automatically at the press of a button or by remote control. Four of the five available petrol engines were new in the Mercedes‑Benz Convertible. The performance range of the four, six and eight-cylinder engines ranged from 120 kW (163 hp) to 270 kW (367 hp); fuel consumption decreased by up to 7 per cent.
With its fascinating styling, developed from the design of the successful Coupé, the new Convertible also emphasised the independent character of the CLK-Class in the passenger car line from Mercedes‑Benz. Each detail of the dynamically and elegantly drawn body and of the tasteful interior justified the claim to the utmost exclusivity.
Only a single motion of the hand sufficed for opening the black, blue or grey convertible soft top: the customer needed only to press the distinctive pull-push button switch on the centre console or use the remote control in the electronic key, and a few moments later the hydraulics would set the top in motion. Before the soft top vanished in the rear of the CLK Convertible under the cover designed with so-called 'air domes', the fully retractable side windows automatically opened. Nor did closing the soft top require any operations other than pressing a button on the centre console; the hydraulics performed this task and automatically locked the roof within 20 seconds at the upper frame of the windscreen. While the soft top was in motion, an indicator lamp in the soft-top switch lit up, and flashed if the top was not properly locked during driving. In this case a warning chime simultaneously sounded. The automatic soft top mechanism operated at vehicle speeds of up to 8 km/h.
The three-layered upholstery of the soft top provided exemplary heat insulation and kept driving noise in the interior to a very low level. The slender C-pillars as well as the large side and rear windows afforded the driver a flawless rear view even with the soft top up. The new CLK Convertible was at the head of its class regarding interior noise, thermal insulation and 360-degree visibility.
The boot capacity increased by 40 to 390 litres (according to the VDA measuring method, with the soft top closed) compared with the predecessor - also a best value among four-seater convertibles. With the roof open the capacity of the luggage compartment was 276 litres. Just like the soft top, the boot lid could also be opened by remote control. The boot lid was also among the innovations of the convertible body. Here high-quality plastic provided a benefit significantly contributing to the elegant appearance of the convertible: thanks to the high-tech material, the antennas for short, medium and long-wave reception by the car radio as well as for the optional car telephone and navigation system could be discreetly integrated in the boot lid. A conventional steel construction did not allow this for reception reasons. Other antennas were located in the windscreen.
Other equipment features of the new CLK Convertible typical for the high claims of the Mercedes-Benz brand were the sensor-controlled roll-over protection that automatically extended within a fraction of a second in the event of danger, and the large head/thorax side airbags in the backrests of the front seats. Emergency belt tensioners and belt-force limiters at all seats, automatic belt extenders for driver and front passenger as well as adaptively controlled front airbags were also standard. The situation-dependent deployment of the front passenger airbag also took into account the co-driver's weight on the right front seat. For the first time, side airbags were also available for the rear.
A rigid body structure provided the basis for exemplary safety and high comfort. Around 40 per cent of all sheet metal panels of the bodyshell were made from high-strength steel alloys offering maximum safety and stability with a minimum of weight. The torsional rigidity of the body - an important indicator of handling characteristics and vibration-related comfort - further improved by about 12 per cent over the predecessor model. In other words, despite the absent roof structure, the body structure of the CLK Convertible attained a rigidity corresponding to the high level of the coupé. These noteworthy results rested on a series of design-related reinforcement modifications to the floor pan, the longitudinal members, the rear wall as well as the A and B-pillars that differentiated the bodyshell of the convertible from its coupé sister model.
The convertible of the CLK-Class also attained top marks in its category with respect to aerodynamics. Besides a low coefficient of drag of only Cd = 0.30, it boasted exemplary figures for negative lift at the front and rear axles. The aerodynamics thus afforded an important basis for high driving stability, optimal noise comfort and low fuel consumption.
Open-air driving pleasure along with top comfort for four passengers - these goals were also realised more consistently than by the predecessor. Thanks to a body larger in all dimensions (71 millimetres more in length) and the longer wheelbase (an additional 25 millimetres), the 4.64-metre-long two-door car afforded its occupants significantly more space and comfort. For example, the front headroom increased by 23 millimetres, the elbow width in the rear by 30 millimetres and the knee room of the rear passengers by nearly 44 millimetres.
A further developed easy‑entry system facilitated passengers' entry to the rear, where comfortable, bucket-shaped individual seats awaited them. They were fitted with integrated automatic seat belts and vertically adjustable head restraints that could be lowered nearly all the way by pressing a button on the instrument panel.
In addition, the standard equipment of the CLK Convertible included other systems significantly enhancing ride comfort and operating convenience: automatic climate control, Headlamp,p Assist, rain sensor for the windscreen wiper, cruise control with SPEEDTRONIC, car radio with cassette player, horizontally and vertically adjustable multifunction leather steering wheel with illuminated control buttons as well as central display for personal settings.
Innovations from the top Mercedes‑Benz models made the CLK Convertible a high-tech car unique in this vehicle category. Optional extras included DISTRONIC adaptive cruise control, KEYLESS GO keyless access & drive authorisation system, APS COMAND operating and display system, LINGUATRONIC voice control for telephone, car radio and navigation, THERMOTRONIC automatic climate control with sun sensor and high-intensity bi-xenon headlamps.
As in the coupé, Mercedes‑Benz customers could also choose between two lines for their CLK Convertible - ELEGANCE and AVANTGARDE - and in this way realise their personal desires regarding design and equipment. Eleven metallic and two standard colours were available for the body. For even greater customisation, from mid-2003 Mercedes‑Benz offered twelve metallic colours in its designo line, up to eleven colours for the leather interior and three for the trim. This exclusive line of options was rounded off by fine Alcantara covers for the A-pillars and the roof frame, available in three colours.
Individuality and diversity also applied to the line of engines: five state-of-the-art petrol engines were available. They differed from the engines of the predecessor model by a considerable increase in power, by higher torque and by lower fuel consumption.
At the top of the line were two eight-cylinder engines with the power characteristics of pedigree sports cars: the CLK 500 developed 225 kW (306 hp) and accelerated the convertible from 0 to 100 km/h in 6.2 seconds, becoming more powerful by 20 kW (27 hp) and faster in acceleration by 1.2 seconds than the previous CLK 430. Despite the greater power, it consumed around 5 per cent less fuel than its V8 predecessor. From Mercedes‑B enz AMG came the 270-kW (367-hp) V8 engine of the CLK 55 AMG, with 15 kW (20 hp) greater output than in the predecessor model. The Convertible sprinted from 0 to 100 km/h in only 5.4 seconds (predecessor: 6.2 seconds), with an electronically limited top speed of 250 km/h. A perfect supplement to the dynamic power delivery was the five-speed automatic transmission with AMG‑SPEEDSHIFT. In manual transmission mode it could be operated in racing-car style at the push of a button on the steering wheel. In addition, the gears did not change automatically here, so that the driver could ideally exploit the high tractive power even at wide open throttle. The CLK 55 AMG was equipped with a high-performance braking system, AMG sports suspension, AMG light-alloy wheels (18 inches) with the attractive double-spoke design as well as wide-base tyres of size 225/40 at the front and 255/35 at the rear. The AMG Bodystyling package consisted of the front apron with integrated fog lamps, dynamically shaped side sills and a special rear apron.
Mercedes‑Benz expanded its six-cylinder line with the smooth-running 2.6‑litre engine with 125 kW (170 hp). The proven V6 engine of the CLK 320 (160 kW/218 hp) remained available without changes.
The new Mercedes‑Benz four-cylinder engine with the unique TWINPULSE system also led to further progress in the CLK Convertible with respect to power characteristics, torque development, smooth running and fuel consumption. The TWINPULSE system combined different technologies like compressor-type supercharging, balance shafts, charge air cooling, variably adjustable camshafts and four-valve technology. With this high-tech package under its bonnet the new CLK 200 KOMPRESSOR generated 120 kW (163 hp) with the running smoothness of a six-cylinder engine and consumed only 8.8 litres of premium petrol per 100 kilometres (NEDC overall consumption) - around 7 per cent less than its equally powerful predecessor.
The new CLK Convertible generation transmitted power either with a six-speed manual transmission or an electronically controlled five-speed automatic transmission with Touchshift.
A suspension system newly or further developed in many respects perfected the dynamic driving experience. With its new three-link front axle, the precise rack-and-pinion power steering and the modified independent multi-link rear suspension, the CLK Convertible offered an ideal combination for optimal driving safety, responsiveness and comfort. A suspension with an even sportier, and therefore firmer, setting of the springs and shock absorbers as well as a lowered body was optionally available.
Standard 16-inch light-alloy rims and mixed tyres at the front and rear axles (205/55 R 16 and 225/50 R 16, respectively) underscored the sporty character of the new Mercedes‑Benz convertible. The V8 CLK 500 rode on 17-inch tyres, and the CLK 55 AMG emphasised its extraordinary character with 18-inch wheels.
In mid-2004 Mercedes‑Benz again significantly upgraded the successful CLK-Class with respect to technology, look and equipment: for example, the Convertible now also had DIRECT CONTROL technology, distinguished by modified axle bearings, more direct steering and shorter shift travel, and allowed even more dynamic handling with no change to the high level of ride comfort. The optional steering-wheel shift buttons for automatic transmission models, new audio equipment with European-wide navigation and bi-xenon headlamps with cornering light function also increased driving pleasure and provided greater safety. Thanks to the worldwide unique 7G‑TRONIC seven-speed automatic transmission - standard on the CLK 500 top model - the fuel consumption of the CLK 500 decreased by up to 0.6 litres per 100 kilometres. In the interior newly designed controls provided even greater value appeal.
The standard six-speed manual transmission was also overhauled: the DIRECT CONTROL technology with shorter shift travel allowed fast and precise gear changes. For the first time, the CLK-Class was available with run-flat tyres, which Mercedes‑Benz combined with an automatic tyre pressure loss warning system. This system was based on the technology of the ESP® Electronic Stability Program and displayed a warning in case of sudden pressure loss in one of the tyres. Thanks to self-supporting tyre side walls, the driver could then continue the journey for up to 50 kilometres at a maximum speed of 80 km/h.
The model refinement also gave the CLK 55 AMG an even more efficient braking system as well as a new sports exhaust system with two distinctive dual tailpipes. A more intensive driving experience was moreover guaranteed by the modifications to the suspension and power transmission: the firmer spring/damper tuning and the 7 per cent more direct steering provided even better roadholding and significantly greater dynamics.
At the 2004 Paris Motor Show Mercedes‑Benz presented the exclusive special series of the CLK 500 Convertible, designed in the style of Italian fashion designer Giorgio Armani. The colour and material concept lent the Convertible a particular aesthetic character. The special matte designo magno paintwork in the warm 'sabbia' sandy tone with subdued greenish shades as well as a harmoniously coordinated interior of valuable materials made the creation exude both refinement and sporty masculinity. For example, in the interior Armani combined a satin high-tech foil, valuable saddle leather and high-tech textiles with brown designo leather. Only 100 of these elegant vehicles were offered worldwide in the designo line, so that sophisticated customers could customise their Mercedes‑Benz models.