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2011 Mercedes-Benz E550 Cabriolet review: 2011 Mercedes-Benz E550 Cabriolet

2011 Mercedes-Benz E550 Cabriolet

Wayne Cunningham Managing Editor / Roadshow
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
Wayne Cunningham
7 min read

Photo gallery:
2011 Mercedes-Benz E550 Cabriolet

2011 Mercedes-Benz E550 Cabriolet

2011 Mercedes-Benz E550 Cabriolet

The Good

The adaptive cruise control system in the 2011 Mercedes-Benz E550 Cabriolet can bring the car to a complete stop and is also integral to its collision mitigation system. Sound quality is very detailed from the Harman Kardon audio system. The navigation system dynamically routes around traffic.

The Bad

The convertible top affects trunk space. The big V-8 turns in mediocre mileage.

The Bottom Line

The 2011 Mercedes-Benz E550 Cabriolet brings a solid cabin tech package to open-top cruising, but the big engine means it will be expensive to run.

With its taut driving feel, the 2011 Mercedes-Benz E550 Cabriolet shows that the company can be serious about sports performance, an area traditionally dominated by BMW.

Mercedes-Benz updated the E-class for the 2010 model year, offering coupe and sedan versions. The Cabriolet is a new version for 2011, offering open-top driving in a midsize sport luxury vehicle. Unlike competitors, Mercedes-Benz sticks with a soft top for the E550 Cabriolet, rather than the retractable hard tops coming into vogue.

Similar to some of the retractable hard top cars we've seen, such as the Infiniti G37, the E550 Cabriolet suffers from a trunk space deficit to accommodate the top. But Mercedes-Benz employs a few tricks to make its convertible very livable.

A deflector rises up from the top of the windshield frame to channel air over the cabin.

A headliner inside the canvas helps deaden exterior noise and keeps the cabin's look consistent. Mercedes-Benz's Air Scarf technology uses fans in the headrests to blow warm air on front passengers' necks, making top-down driving in colder weather comfortable. The car also attempts to lessen turbulence in the cabin with a special deflector that rises up from the top of the windshield frame.

Tight sound
An optional Harman Kardon audio system made listening to music in the car an enjoyable experience, with the top up. But this system does not adapt well to top-down driving. To hear the system while driving at 50 mph on a highway, we had to put up the side windows. Other automakers use digital signal processing and other tricks to adapt audio for convertibles.

When we could hear it, this audio system, using 12 speakers and 450 watts of power, produced finely detailed sound. Well-balanced bass was strong but not overwhelming, and highs were delicate without being too bright. We listened to a variety of music, from acoustic with clear vocals to complexly layered electronic tracks with subtle sounds. Overall, the audio had a very contained quality, sometimes seeming too tightly presented where we would have preferred a more expansive sound.

Two of the audio system's 12 speakers sit exposed on this back deck when the top is down.

Mercedes-Benz has yet to include Bluetooth streaming audio as a source, but we were satisfied with the onboard 6GB of music storage, HD and satellite radio, and iPod integration, our only complaint being that the iPod cable is inconveniently placed in the glove compartment, not an easy reach if you want to unplug the device at every stop. There is also a PC Card slot, a strange choice these days.

The interface for music selection takes a little getting used to, as the menu labels can be misleading. But we were happy with the responsiveness of the system. One miscue is that the onboard music library only shows folders, without indexing music by ID3 tags, as the iPod library does.

Although the E550 Cabriolet does not have Bluetooth streaming audio, there is a Bluetooth phone system. We found no trouble pairing an iPhone with the system, and having it download our contacts to the car. These contacts were then available onscreen and through the voice command system, which let us dial by saying a contact's name. This system lacks any text message functions.

Stylish maps
The majority of the car's hard-drive space is reserved for the navigation system's maps, which appear in 2D and 3D. These maps use a refined look with muted colors. The system renders landmark buildings in urban areas, and presents traffic flow in yellow and red, along with icons for specific traffic incidents.

The navigation system uses traffic information for driver alerts and to adjust the route.

The navigation system dynamically changes the route to detour around particularly bad traffic, and issues a verbal warning for merely slow traffic traveling anywhere from 25 to 45 mph on the freeway. Fortunately, the verbal traffic warnings can be turned off, because on the approach to the Bay Bridge in the San Francisco area, it piped up about every 10 minutes to warn us of multiple slowdowns.

The E550 Cabriolet gets a particularly good POI database that proved easily searchable. Not only did it offer locations of many retail establishments, it also listed wineries, something we found useful in California. Zagat ratings for restaurants are included.

We like this navigation system's route guidance, which shows easy-to-follow graphics along with very clear lane guidance. It also reads out street names, making it possible to navigate by ear. A display in the speedometer also shows route guidance, among other choices such as audio and trip information.

This display in the speedometer shows the distance to cars on the road ahead.

The speedometer display also showed a graphic of distance to other cars ahead of us, as our E550 Cabriolet came equipped with Mercedes-Benz's adaptive cruise control. This very convenient system lets you set a cruising speed, then uses forward-looking radar to detect slower-moving cars ahead, matching your speed to theirs. With the system activated, we were impressed that it could bring the car to a complete stop, and let us choose from three following distances.

Radar from the system is also used for Mercedes-Benz's Pre-Safe technology, which automatically tensions the seatbelts and hits the brakes if it thinks a collision is imminent. Pre-Safe seemed a little touchy to us, as it occasionally gave its initial warning and seatbelt tensioning as we drove with a row of parked cars on the outside of a turn, or went from the dark shade of an underpass to bright sunlight. But during these false alerts it did not go into its braking stage.

Sport performance
As its name suggests, the E550 Cabriolet's engine is a 5.5-liter V-8, which Mercedes-Benz introduced with its S550 in 2006. With 382 horsepower and 391 pound-feet of torque, the E550 steps off the line fast enough to threaten its rear-wheel grip. During our fast starts, it felt like Mercedes-Benz tuned the car to the very edge of where the tires would break loose.

The E-class is also available as the E350 Cabriolet, using a 3.5-liter V-6. In other Mercedes-Benz models we've tested, this engine felt a little poky. The V-8 is certainly more satisfying, but it also sucks down the gas. EPA ratings for the car are 15 mpg city and 22 mpg highway. We never saw the trip meter go above 20 mpg, even with a long freeway trip thrown in, and ended up with an overall average of 18.4 mpg.

This V-8 doesn't push the efficiency envelope, lacking technologies such as direct injection or turbocharging. The power train's saving grace is its seven-speed automatic transmission, with gears tall enough to let the engine run under 2,000rpm even when the car's speed is 75 mph.

The seven-speed automatic transmission includes a manual mode, activated by touching the M button.

The transmission includes both standard Drive and Manual modes, with paddle shifters for manual gear changes. Although not terribly snappy, the transmission shifted reasonably fast when we pulled the paddles. An M button near the shifter puts the transmission into Manual mode, where it seemed happy to let us get the engine speed up toward redline.

The E550 Cabriolet also had a Sport button on the center stack, somewhat lost among buttons for seat cooling and heating. When engaged, this Sport mode sharpened the throttle response, giving the car a touchy, thoroughbred feel, with minor throttle input yielding big results.

The suspension is conventional, and tuned more for sport performance than luxury. We liked how well it kept the car hunkered down in turns, the steering wheel responding with a very precise feeling. And in particular, we noted the car's willingness to let its hair down when pushed in the turns, the back end feeling loose and ready to party. Where BMW's allow an amount of rear slip you can practically measure, the E550 Cabriolet seemed less constrained.

Some of that playfulness may have been because of the 18-inch AMG wheels, fitted with all-season performance tires, which came with the car as part of an Appearance package. These wheels might have also affected the ride quality, which was just a little harsher than we would expect from a Mercedes-Benz. We wouldn't call the ride rough, but there is a sports car rigidity apparent.

In more sedate driving, running errands in an urban environment, for example, we were pleased to find a tight turning radius with the car, allowing easy parking lot maneuvering and U-turns on streets.

In sum
It's hard not to like a convertible, and the 2011 Mercedes-Benz E550 Cabriolet has a lot to offer beyond open-top driving. Mercedes-Benz did a good job on external styling, always a challenge when replacing the top of a car with cloth. But the squashed trunk space removes some of the practicality, and though we have gotten used to the cabin tech interface, the design is somewhat quirky.

The car offers a taut driving feel, achieving sports car handling beyond Mercedes-Benz's past efforts. But in these days of direct injection and turbocharging to heighten fuel economy, the engine seems a little basic. The seven-speed transmission is a tech win.

Mercedes-Benz's cabin tech has some excellent qualities, but it does not push any boundaries. Lacking are any external data sources besides traffic, such as weather or fuel prices. High points include the Harman Kardon audio system and the adaptive cruise control, one of the best in the business. Cell phone and MP3 player connectivity is no better than in cars costing substantially less.

Tech specs
Model2011 Mercedes-Benz E-class
TrimE550 Cabriolet
Power train5.5-liter V-8, seven-speed automatic transmission
EPA fuel economy15 mpg/22 mpg
Observed fuel economy18.4 mpg
NavigationHard-drive-based with traffic
Bluetooth phone supportStandard with contact list import, dial by name
Disc playerMP3- and video-compatible six-disc changer
MP3 player supportiPod integration
Other digital audioOnboard music library, PC Card, satellite radio, HD Radio, auxiliary input
Audio systemHarman Kardon 12-speaker 450-watt Dolby Digital 5.1 system
Driver aidsAdaptive cruise control, rearview camera, park distance warning
Base price$64,800
Price as tested$77,425
2011 Mercedes-Benz E550 Cabriolet

2011 Mercedes-Benz E550 Cabriolet

Score Breakdown

Cabin tech 8Performance tech 7Design 7


See full specs Available Engine GasBody style Convertible