2008 Mercedes-Benz ML550

2008 Mercedes-Benz ML550 Quick Facts

Base Price:	$52,400
Price as Tested:	$67,800
Horespower:	382 Hp @ 6000 rpm
Torque:	391 lbs-ft @ 2800 rpm
0 to 60:	5.6 seconds
ABS Brakes:	Standard
Side Curtain Airbags:	Standard
EPA Fuel:	13/1 m.p.g. city/highway
Towing Capability:	Yes
Off-Road Capability:	Yes
First-Aid Kit:	Not available
Notes/Additional Info.:	Base price on the test car is $52,400. Option packages add almost $15,000. The test car has a MSRP of $67,800, including the $775 destination charge.

The M-Class is an a la carte offering that can fill lots of squares. Depending on the grade and options, it can function as a sport-utility vehicle with luxurious appointments, or a sports car with a very large cargo area. A clean diesel model makes it a green car as well.

The ML550, equipped with a 382-horsepower V8 engine, is the sports car in the M-Class family. With a zero-to-sixty time of 5.6 seconds, it makes quick work of weekly grocery shopping.

While the test car has many off-road handling features such as permanent four-wheel drive, hill start assist, and downhill descent control, an AMG sport package makes it more a car for the streets. The AMG option upgrades the standard wheels and tires to nineteen-inch rims, adds special running boards and restyled front and rear bumpers. In general, I don't like running boards on off-road cars: they have a way of attracting rocks, and ending up on the side of the trail.

But on paved roads, the ML550 combines the performance of a European luxury sedan with the cargo capability of a sport-utility vehicle. The seven-speed automatic transmission comes with a unique shift lever on the steering column that operates with the touch of a finger. Additional steering wheel mounted buttons allow the driver to change gears manually.

The electronic system uses computer controls to adjust shift points according to the driving situation. As with electronic steering and braking, there's a certain leap of faith in abandoning the traditional mechanical systems. But if any company has the engineering finesse to make electronic systems bulletproof, it's Mercedes-Benz.

A fully independent suspension coupled with power rack-and-pinion steering gives the car a buttery smooth ride with excellent steering response at all speeds. The test car has optional air suspension, as part of the premium III package that also includes a bunch of interior upgrades, bi-xenon curve illuminating headlamps, headlamp washers and a power liftgate ($8500).

The Airmatic suspension incorporates adaptive damping that makes real-time adjustments to the shocks depending on the driving situation. Despite its compliant ride, the M-Class stays flat in the corners, even at high speeds. I tested it on some decreasing radius cloverleafs, and the car refused to come unglued.

I still find brake-by-wire a little grabby during sudden stops. But under normal conditions, it feels about the same as a mechanical system.

There's a backup hydraulic system that takes over if the brake-by-wire fails. For an old-fashioned duff like me, there's security in brake fluid. Standard antilock braking, traction control and electronic stability program help the driver maintain directional control on wet or uneven road surfaces.

The bi-xenon headlamps provide a long beam of light--close in color and intensity to daylight. The turn illuminating feature makes pedestrians and cyclists crossing at intersections easier to see.

Standard rain-sensing wipers automatically adjust wiper speed, so the driver doesn't have to switch the wipers on and off in intermittent rain.

A stalk near the turn signal engages the cruise control. I find the proximity of the two stalks disconcerting: it's too easy to mistakenly turn on the cruise control.

A Parktronic rear backup warning system ($770) adds a camera with a wide angle lens that displays the area behind the car in the navigation screen. Not only does the system eliminate blind spots to the rear of the car, it also makes it much easier to back into a small space.