The navigation option itself offers basic functionality but not the advanced features we are starting to see in other cars. If you are not zoomed in all the way on the map, it generally doesn't show street names, which can be annoying, and when it does, the letters often have jaggy edges, making diagonal names difficult to read. But route guidance is accurate, and the LCD graphics get supplemented by a display in the center of the speedometer, which shows basic guidance directions. The points-of-interest database includes the usual run of travel-related places, such as restaurants and gas stations. One feature we like is called Today's Plan, which lets you add multiple destinations, then click a button to find the most optimal route to each place. It can even compute the route as a round-trip.
The stereo is another example of older tech. Our car had the six-disc changer option, which meant a glove-box-mounted cartridge player. At least it wasn't in the trunk. Both the six-disc changer and the single-CD slot behind the LCD play MP3 CDs, but the display can only show file names, not full ID3 tagging information. Sirius satellite radio is also an option, and Mercedes-Benz mounted an auxiliary audio input inside the glove box. An iPod integration kit is available, but wasn't present on our tester. The audio system is by Harmon/Kardon, and it sounds good, but not fantastic. In the CLK550 Cabriolet, this audio system only has six speakers--centerfill, subwoofer, and four door woofers--which seems to limit audio qualities such as separation. Although we like that you can move the audio sweet spot anywhere around the cabin, the fact that you have to use the little joystick to do it means it will never be exactly centered.
As with the last generation of Mercedes-Benz cabin electronics, this one relies on a cell phone cradle system for hands-free calling. The dock for the cradle sits at the back end of the console, and will continue to look ugly and go unused in most of these cars. As we saw with the C300, Mercedes-Benz has embraced Bluetooth for its future cabin gear, so it might be worthwhile to wait for an upgrade to the CLK550 if you are interested in buying.
Under the hood
Much like we've seen the cabin electronics in previous Mercedes-Benz models, we've used this engine in other models we've reviewed. The CLK550 gets the 5.5-liter V-8 we first saw in the S550 last year. In the CLK550, its 382 horsepower pushes it to 60 mph in 5.2 seconds, according to Mercedes-Benz. We can believe that. In our driving, this engine had plenty of power on tap--whether we were on the freeway, going uphill, or driving backroads, we never lacked power. But that power comes at a price. The CLK550 gets an EPA-rated 15 mpg city and 21 mpg highway, subjecting it to the $1,000 gas guzzler tax. During our driving, we observed an average of 18.7 mpg, not great mileage but not much below what we've seen in V-6 sedans. Although emissions ratings for the 2008 Mercedes-Benz CLK550 Cabriolet hadn't been published at the time of this review, the 2007 Mercedes-Benz CLK550 Coupe got a ULEV II rating, one better than the minimum.
During our time with the CLK550 we took it on a cruise from San Francisco to Concord, about 30 miles east. Instead of taking the boring freeway, we went up through the Oakland hills on various roads with names such as Wildcat and Grizzly Bear appended to Canyon and Valley. For the most part, these roads let us negotiate long, sweeping curves and straight-aways where we could let the car run. The suspension in the CLK550 can go from Comfort to Sport mode at the push of a button. We kept it in Sport, where it went noticeably rigid, limiting body roll while cornering.
The steering wheel turned without effort as we dove into each turn--the steering is a little light for our tastes, offering minimal feedback about the road. But the big tires gripped without effort, and the big power plant made it easy to pull through a turn or pass slower vehicles on the straightaways of this two-lane road. Along with the 5.5-liter V-8 comes Mercedes-Benz's seven-speed automatic transmission, manually shiftable with a side-to-side motion on the stick or using the paddle shifters mounted to the wheel. We didn't find the manual shift experience terribly responsive--there was always a noticeable lag between the time we made the shift and felt it, which limits some of this car's sporting potential.
The convertible version of the 2008 Mercedes-Benz CLK550 comes in at a base price of $62,900. Among our options were the $2,290 navigation system and the $3,720 Premium 3 Package, which included the Driver Multicontour Seat, the Harmon/Kardon audio system, and the six-disc changer. Along with its $775 destination charge and $1,000 gas guzzler tax, the total price came out to $73,035.
We enjoyed driving the CLK550 quite a bit. It has lots of power on tap and the steering is responsive. And who doesn't like cruising around in a convertible? But the cabin gadgets aren't exactly cutting-edge, and we find the cartridge-style six-disc changer particularly laughable. The bodywork on the car isn't particularly striking, either, even with the AMG wheels and styling we had on our tester. For less money, you could be in a BMW 335i hard top convertible, which has better cabin electronics. But the CLK550 has the more comfortable interior.