They range from the CLK320 with performance that is sporty, poised and stately, to the powerful CLK430 to the ridiculously fast CLK55 AMG. The coupe's lines are tidy and classic, while the cabriolet features a soft top that is so nicely finished inside and so quiet when it's up, that you'd swear you were in the coupe.
All CLK-Class models combine graceful looks with luxury, power, performance, and technology. Lean and quick, they perform wonderfully. They feel solid and motor around corners like they're on rails. These are terrific cars. The CLK-Class is a good size for owners who rarely need a back seat but want one for occasional use.
CLK320 Coupe ($42,550) CLK320 Cabriolet ($49,600) are powered by a lightweight and sophisticated 3.2-liter sohc V6, delivering 215 horsepower and 229 pounds-feet of torque. Like all CLKs, it comes with a five-speed automatic transmission, which makes for a superb combination. The CLK320 offers a perfect balance of ride and handling, smooth high-speed cruising, and responsive acceleration performance. CLK320 comes with seven-spoke 7x16-inch forged light-alloy wheels with 205/55HR16 tires.
CLK430 Coupe ($50,250) and CLK430 Cabriolet ($57,300) are powered by a 275-horsepower 4.3-liter V8; it's basically the V6 with two more cylinders. They wear 7.5x17-inch front and 8.5x17-inch rear alloy wheels with 225/45ZR17 front and 245/75ZR17 rear tires.
CLK55 AMG ($68,450) and CLK55 AMG Cabriolet ($79,000) boast a 5.5-liter V8 producing 342 horsepower and a humongous 376 foot-pounds of torque.
CLK320 models have full body-color bumpers, air dam, and rocker panels. Chrome is limited to the grille and door handle trim. CLK430 models receive AMG-designed Sport aerodynamic enhancements, black window trim, blue-tinted windows, and new five-spoke wheels. CLK320 models are available with a Sport package ($4,600) that incorporates AMG aerodynamic bodywork and 17-inch wheels and tires.
The CLK55's 17-inch AMG alloy Monobloc wheels are aptly named. They're very full, yet remarkably easy to not notice. But because they don't draw attention to the car, they allow a low personal profile. The CLK55 AMG does not shout "Look at me!" But when you do, you whistle. The wide-profile Michelin Pilot tires are swallowed by fenders that have virtually no flares, yet the CLK55 AMG doesn't look wide. The stance is understated and belies the power. The two-wide chrome exhaust tips that exit together under the left taillight are the only real hint of the 342 horsepower.
The CLK boasts room for four with outstanding seats that are handsomely finished. The front seats are firm and supportive with 10-way power adjustments. Adjustments work fluidly and it's easy to find a comfortable position. Three-position memory buttons on the driver's door includes settings for the seats and outside mirrors. The CLK55 AMG gets special multi-contour heated seats with pneumatic side, lumbar, and thigh supports, but we found there wasn't enough side bolstering for a car that corners with such g-force.
All CLK-Class models come equipped with a full complement of luxury features: leather upholstery with fine wood trim, dual-zone climate control, Bose sound system, dual heated power outside mirrors. The leather-trimmed steering wheel telescopes manually and features nice audio and telephone controls that are soft to the touch.
The interior is not, however, traditional Mercedes in terms of decor: there's warmth in the interior color scheme. Mercedes has emerged from a long tradition of funereal hues and dark wood trim into something more contemporary. The leather upholstery is available in ash, oyster, and charcoal. Wood trim is tastefully used on the doors, dash, front console and shift gate; the strip of wood across the very top of the dash may escape attention at first. The CLK320 uses burl walnut, while the CLK430 and CLK55 come with black Birdseye maple wood trim.
It isn't a perfect interior, however. The glove box is small. Window switches are on the center console instead of on the driver's doors where they would be easier and quicker to find and operate. The stereo is brilliantly designed and the telephone integration makes us want it fully set up for a telephone. However, the trunk-mounted CD changer awkward and less convenient than an in-dash CD changer, and it takes up space in the tiny trunk.
Getting into the rear seat of coupes isn't always easy, but the Easy Entry system automatically moves the front power seats forward, then returns them to their original position. The front seats have enough fore-aft adjustment to move all the way back flush against the rear seats, eliminating rear leg room. A little cooperation from the front passengers, however, makes for a reasonably comfortable rear seat for going to a restaurant. Two adults will find ample leg, knee and shoulder room in the rear seats. The convertible top makes Cabriolets much more cramped in terms of rear-seat legroom, hip room and head room.
Cabriolet models get an excellent soft top that's so quiet when it's up you'd swear you're in a hard top coupe. Look up and the roof liner is so elegantly finished that you'd still swear it's a hardtop. The main giveaway is the release handle. Retailers usually give CLK customers a 90-minute Walkaround on these cars; be sure to take advantage and pay attention to operating this top as it's a fairly complicated process.
Visibility is compromised in Cabriolets by the small rear window. Small outside mirrors don't help as much as they could; bigger mirrors would be better. Power rear headrests are handy, allowing the driver to press a button to raise them for rear passengers or lower them for better visibility.
Passive safety features found in Mercedes-Benz cars are among the best in the world, and include side-impact airbags. Cabriolets are fitted with a roll bar that automatically pops up to protect occupants should you roll the car onto its roof. Be sure to wear seatbelts because they are superbly engineered in the Mercedes with pre-tensioners and force limiters, which help reduce injuries. The Tele Aid system, which comes standard, detects an accident and summons police, fire, and emergency services to the scene whenever an airbag deploys and the driver does not respond.
Trunks are small, just 11 cubic feet in CLK coupes. CLK Cabriolet trunks are hopelessly small, just 9.4 cubic feet, no bigger than the trunk in the tiny SLK roadster. Put the top down and the CLK's trunk shrinks to a tiny 5.7 cubic feet, just slightly larger than a Mazda Miata's trunk.
At low speeds, the CLK320 feels stately, like a Mercedes-Benz. The ride quality is firm. It smoothes bumps and uneven pavement yet leaves the driver feeling connected to the road. You will hear and feel bumps, however; Mercedes doesn't soften them as much as Lexus.
Drive the CLK harder and you'll discover the handling is sporty with little understeer, that phenomenon of the front wheels sliding before the rear wheels that's so prevalent in the cars from Japan. Charge into a corner a bit too fast and lift off the throttle and you'll get some trailing-throttle oversteer. In other words, this car handles like a sports car. The CLK320's tires feel smooth and quiet. However, for hard driving, the 205/55HR16 Continentals do not offer the ultimate in high-performance grip on dry pavement.
ESP, the electronic stability program, works phenomenally well. It helps keep skilled and unskilled drivers on the road, in dry or slippery conditions. Go into a corner too fast for the conditions and the anti-skid system maintains handling balance the way a highly skilled driver would. ESP can detect an impending spin or slide and prevent it by applying selective braking (to one wheel) to keep the car going where the driver is pointing it. And ESP in no way diminishes the sporting character of the car, the way some anti-skid systems do. A switch on the dash allows the driver to turn the system off, but few will ever wish to do so and in few situations. Even on a race track, I might be inclined to leave it on for the familiarization laps. We tried it out on dry corners and on icy patches where it made the car far easier to handle, adding to our confidence.
ESP works with the rest of the CLK's standard active safety features, which sound like alphabet soup but can save your life. These systems are particularly well engineered by Mercedes and are among the best in the world. ASR provides straight-line traction control, helping the driver accelerate on slippery surfaces by selectively applying one of the rear brakes or reducing power whenever it detects a rear wheel is spinning.
The brakes are excellent, easy to modulate. CLK320 and CLK430 use the same four-wheel anti-lock disc brake system. ABS allows the driver to brake and steer at the same time in an emergency stopping maneuver. Brake Assist applies full braking in an emergency stop if it detects the driver is incorrectly easing off the brake pedal when he or she feels the anti-lock brakes pulsing through the brake pedal, a common driving mistake.
The CLK's five-speed automatic transmission is smooth and responsive, always in the right gear, and you may never feel the need to use its Touch Shift feature. Standard on all models, Touch Shift allows the driver to manually select all five gears by pushing the lever slightly left to downshift or right to upshift. It stays in the Drive selector position, so it isn't necessary to move it over into a separate gate like with most of these auto-manual shifters. The CLK's five-speed automatic is adapted from the strong transmission used in the V12 S-class models. CLK320 models use a different set of ratios than the V8-powered CLK430 and CLK55 AMG.
CLK320's 3.2-liter V6 engine is smooth and quiet. It delivers more than enough performance to satisfy even spirited driving enthusiasts. Producing 229 pounds-feet of torque from 3000 to 4600 rpm, it can sprint from 0 to 60 mph in just 6.9 seconds, performance on par with some V8s. While driving it, we did not feel we were missing out by not having the CLK430's powerful V8.
CLK430's 4.3-liter V8 sustains 295 pounds-feet of torque over a large plateau from 3000 to 4000 rpm, giving this car tremendous punch. The result is 0-60 mph in just 6.1 seconds.
CLK55 AMG rockets to 60 mph in a scant 4.9 seconds (5.9 seconds for the Cabriolet) with its 5.5-liter V8 hand-assembled by AMG. That's worth the price of admission just for those pedal-to-the-metal freeway on-ramp assaults. Of course, you'll be breaking the speed limit before you reach the slow lane. You can hit the rev limiter at 6000 rpm in a heartbeat. Since peak power is 5500, you want to shift before 6000. In Touch Shift, you find yourself short-shifting a lot to stay with the engine because it's hard to watch the tach that much. It may be better to stay in the automatic mode until you get in third gear.
The rumble of the big CLK55's V8 is audible, and satisfying. Maybe 332 cubic inches isn't old-school big, but the engine sounds bigger than that, and the torque makes it feel much bigger. When you hammer this baby, it gets hammered good. But it likes to have the throttle rolled, not hammered. The engine delivers huge hunks of power without complaint, but the transmission wants you to take your time. Rolling on the throttle provides that time, and the result will be fewer sudden downshifts and a smoother drive. Because the electronic programming of the transmission is networked with the ESP (electronic stability program) for directional stability, even cornering forces affect whether the transmission will shift -- even when it's in Touch Shift mode. The torque converter has its limits, which also come into play when the transmission decides whether to shift.
Nowadays there's not much to be gained by looking under the hood at a powerful engine; it's not like looking down on a 454 Chevy any more. Under the CLK55 AMG hood, what you mostly see is plastic. A huge black air intake box covers the engine, offering intriguing glimpses of plumbing down below. Here's what's you can't see: A super-stiff forged steel crankshaft churns inside the pressure-cast aluminum block of this chain-driven single overhead-cam V8 with two intake and one exhaust valves per cylinder, as well as 16 coils and 16 spark plugs. The complex dual-resonance intake manifold with carefully tuned runners is mostly what delivers the torque, which requires a beefy differential and four-bolt driveshaft that's four inches in diameter. The engine displaces 332 cubic inches, bored and stroked up from the CLK430's 260 cubic inches, and has an explosive compression ratio of 10.5:1.
The CLK55 AMG gets special high-performance brakes. The front vented discs are 13.2 inches in diameter and the rears 11.8, which increases the braking swept area by about 7.6 percent over the CLK320 and CLK430. The rotors are pin-mounted, a racing technique which keeps them cooler. If what you want is to outbrake a BMW M5, don't count on it, however. The BMW has bigger brakes (Tale of the tape: BMW: front 13.6 inches, rear 12.9. Benz: 13.2 front, 11.8 rear). And while the BMW weighs more (Tale of the scale: M5, 4024 lbs; CLK55 AMG, 3444), the Mercedes can't stop like the M5 when braking hard from 90 mph to 30 mph to set up for a corner. Compared with the M5, the brakes on the AMG Mercedes seem soft. Generally, the brakes on the CLK55 AMG could be firmer and still be civilized.
The CLK55 AMG's suspension is upgraded with stiffer springs, tighter shock valving, thicker stabilizer bars and firmer suspension bushings. It rides on AMG Monoblock alloy wheels, 7.5" front and 8.5" rear, shod with 225/45ZR17 and 245/40ZR17 Michelin Pilots. Ride quality is smooth and comfortable at all times. A BMW M5 should be able to take corners more quickly than a CLK55 AMG. But this isn't a race, it's about driving. The suspension compromises made by the CLK are gentlemanly, and in keeping with its drop-dead gorgeous looks. It likes to be flicked into a turn, meaning it's fun to flick it, but a hard flick doesn't always end exactly at the end of the flick. On an uneven surface in a sweeping corner, the CLK may twitch just enough to keep you honest and under control and out of jail. It never suggests that it might like to take control from you, it teases and excites you. The twitch that comes under real hard braking on uneven surfaces is less secure. But we're talking really hard braking.
At the other extreme of the springs, the CLK can be so light on its feet that they feel like they leave the ground. We thought "Wheee!" when we saw the traction control light flutter as we crested a hump on a two-lane at high speed, especially when we knew the touchdown would be secure.
AMG is Mercedes' high-performance car-building partner and the group that builds and campaigns the sports racing cars. The CLK is an excellent platform for this treatment. Considering the CLK's beauty, balance and size (16.4 overall inches shorter and nearly 800 pounds lighter than a comparable CL-Class), an AMG version begged to be built. Give it the best V8 AMG can build, add superb handling, great brakes and magical electronic driving assists, and you have one of the quickest roadgoing Mercedes ever built. The fact that the CLK55 AMG is the Formula 1 racing series' safety car is more than symbolic. It takes a lot of speed and style to look great leading a field of F1 cars around a track, and this car has what it takes.
No one truly needs more power than the smooth, highly efficient 3.2-liter V6 that comes in the CLK320 models, however. And for most of us the powerful 4.3-liter V8 found in the CLK430 is more than plenty. If there is a flaw in the CLK-Class, it is that it does everything so well, it may seem to lack character.
Fat chance, with the CLK55 AMG. It does the high-performance thing so well, and with such style. Trust us, this car has character.
Sam Moses contributed to this report.
Model as tested
CLK320 Cabriolet ($49,600)
4 years/50,000 miles
Bremen, Germany (5.5-liter engine assembled in Affalterbach, Germany)
Gas guzzler tax:
Price as tested
Options as tested
Brilliant Silver paint ($640); K4 Value Added Package ($1,685) includes rain sensor, headlamp washing system, xenon headlamps, heated front seats
Model Line Overview
CLK320 ($42,550); CLK430 ($50,250); CLK320 Cabriolet ($49,600); CLK430 Cabriolet ($57,300); CLK55 AMG ($68,450); CLK55 AMG Cabriolet ($79,000)
Safety equipment (standard)
System, ASR traction control, Electronic Stability Program, BabySmart standard
Safety equipment (optional)
3.2-liter sohc 18-valve V6
5-speed automatic with Touch Shift
Specifications as Tested
leather-trimmed upholstery, 10-way power front seats w/3-position memory, dual zone automatic climate control, AM/FM/cassette stereo with trunk-mounted 6-disc CD changer, power windows, power locks, power seats, heated power mirrors, keyless remote entry, leather seating, split-folding rear seatbacks, cruise control, alarm system, aluminum alloy wheels
Engine & Transmission
3.2-liter sohc 18-valve V6
Horsepower (hp @ rpm)
215 @ 5700
EPA fuel economy, city/hwy
Torque (lb.-ft. @ rpm)
Head/hip/leg room, middle
Head/hip/leg room, front
Head/hip/leg room, rear