Used 2008 Mercedes-Benz S-Class

The flagship sets the standard for a carmaker’s lineup, as it’s a showcase for the best the company has to offer. Though there are a couple of higher rungs on Mercedes’ sedan ladder (the rare, V12-powered S600 and the even more-rare AMG performance models), the 2008 Mercedes-Benz S550 is the mainstream top of the list. With the premium V8 and newly redesigned 4MATIC all-wheel-drive system, the vehicle is equipped with arguably the most popular combination of features to be found on a big Mercedes in the U.S. market.

With premium luxury cars, owners might likely be in the rear seat, being driven, instead of up front, being drivers. It’s a rare car that is equally satisfying in either role, but the 2008 Mercedes-Benz S-Class certainly qualifies. The 5.5-liter V8 makes effortless power and the seven-speed automatic transmission shuttles from gear to gear seamlessly. The combination of the Airmatic Semi-Active air suspension and other details effectively insulates the occupants from outside noise, while not isolating the driver from road conditions, and the 4MATIC, in concert with the Electronic Stability Program and the vehicle’s relentless mass, makes the S550 a reassuringly stable winter driver.

Understated elegance is the theme on the inside of the 2008 Mercedes-Benz S-Class. Amber ambient lighting rings the front cabin and, in the rear, passengers stretch out with 42.3 inches of legroom. One of the challenges that a luxury automaker faces is how to provide access to all the features of a high-end vehicle without undue frustration or driver distraction. The S-Class interior houses a busy but logical array of switchgear. Many functions (navigation, sound system, phone, vehicle) are displayed on an eight-inch color screen in the center of the dash. They’re accessed by Mercedes-Benz’s COMAND system, through a turn-and-push, aluminum knob on the center console. With a modest amount of study time, drivers soon learn to use the mouse-style controller to change navigation, audio, telephone and vehicle settings. Inside storage spots are numerous, if small, and the big trunk is a trip-friendly luggage swallower.

Longer, taller and wider than the previous generation, the 2008 S-Class has a polished, sleek shape. In profile it has a slight nose-down rake, capped by a curvy, coupe-like roofline and with flaring fenders that stretch over wheels positioned near the corners. The sloping front end features a set of asymmetrical headlamps framing the traditional Mercedes shield-shaped grille. C-pillar, fenders and deck lid all converge gracefully at the tri-section, vertical tail lamps. The short deck in back hides the big trunk beneath. In all, it’s a refined, modern look that’s somewhat deceptive. The S-Class doesn’t appear to be all that large—until you park it next to something that isn’t.

Cabin comfort/Ride quality
Whether in the front seats or the rear, the S550 is an enormously comfortable car. The interior is quiet, spacious and accommodating, and the long wheelbase and Airmatic suspension system smooth the edges off the roughest pavement.

Drivability
The responsiveness of the 2008 Mercedes-Benz S-Class belies its size. The silky drivetrain and supple chassis conspire to make this full-size car drive as if it’s something smaller and sportier than its dimensions indicate.

Notable among the standard appointments on the Mercedes flagship is a fine-sounding 14-speaker, 600-watt harmon/kardon(r) surround-sound system that plays CDs, DVDs and MP3s and has a compact flash memory card slot. The hands-free communication system has voice controls for telephone, audio and navigation features. The GPS navigation system includes a 20-GB onboard hard disc and an eight-inch screen that tilts for easier viewing. The power glass sunroof adds a splash of sunshine or starlight, while the power rear-window sunshade affords more privacy. Bi-xenon headlamps include Active Curve Illumination with cornering lights and heated washers.

The list of available features on the S550 includes the Night View Assist system, which extends the driver’s nighttime forward vision by projecting infra-red light onto the road ahead and displaying the reflected image on the eight-inch screen on the instrument cluster. The standard 14-way adjustable heated seats can be supplemented by optional cooling ventilation. Adaptive seats offer four levels of massage and active controls that monitor driving conditions, adding lateral support to seat bolsters to hold passengers in place while cornering. Radar-based Distronic PLUS Adaptive Cruise Control and Parking Guidance systems help the driver maintain a safe distance from other vehicles and objects.

As befits a top-line luxury car, the S550 has a wonderful powertrain. The 5.5-liter V8 is rated at 382 horsepower and 391 lb.-ft. of torque, and its silken power flow meshes well with the smooth, silent shifting of the seven-speed automatic transmission. The combination is capable of accelerating from zero to 60 mph in well under six seconds, which is quite impressive for a car that weighs nearly 4,700 pounds. The S550’s fuel economy is slightly less than its contemporaries, but that’s probably not a major purchase issue.

5.5-liter V8
382 horsepower at 6000 rpm
391 lb.-ft. of torque at 2800-4800 rpm
EPA city/highway fuel economy: 14/21 (RWD), 14/20 (AWD)

5.5-liter V12 Twin Turbocharged
510 horsepower @ 5000 rpm
612 lb.-ft. of torque @ 1800-3500 rpm
EPA city/highway fuel economy: 11/17

6.3-liter V8
518 horsepower @ 6800 rpm
465 lb.-ft. of torque @ 5200 rpm
EPA city/highway fuel economy: 11/17

6.0-liter V12 Twin Turbocharged
604 horsepower @ 4800-5100 rpm
738 lb.-ft of torque @ 2000-4000 rpm
EPA city/highway fuel economy: 11/17

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