2008 Mercedes-Benz ML550 review

Also part of the Premium III package, our car came optioned up with Sirius satellite radio, which, like the iPod interface, we found to be somewhat problematic to program. While it is easy to use the steering wheel arrow buttons to skip between songs within a certain category (such as new country, prime country, and outlaw country in the country category), it does not seem to be possible to change categories without digging down to the relevant menu using the dash-mounted COMAND module, and only then by pushing the joystick to the side while in the Sirius satellite radio screen.

The other major entertainment option on our car was the $2,670 rear-seat entertainment system, which comprises two 7-inch seatback displays set into independent brackets to the rear of the front-seat headrests. The rear-seat system supports DVDs, CDs, and MP3s--inserted in a disc slot beneath the right-hand rear passenger's legs--and comes with two wireless headsets and a dedicated remote control. A cheaper option to keep the backseat passengers occupied is the $1,250 accessory rear-seat entertainment system, which comprises a single seven-inch display installed between the two front seats.

Under the hood
While the ML550 is more than 300 pounds heavier than the S550 and the CL550, the 382-horsepower all-aluminum V-8 still manages to endow it with breathtaking pick-up, particularly when using the Touch Shift controls mounted on the back of the steering wheel. Mercedes says that the ML550 will haul itself from standing to 60 in less than seven seconds--a claim that we were willing to believe after only a few seconds behind the wheel.

It may not be in the same performance league as the 2008 Porsche Cayenne Turbo , but the ML550 displays the throttle response and all-around driving dynamics that belie its ride height. And for those with deep-enough pockets, the midsize SUV can be decked out to look as fast as it drives with the addition of a number of external options, including the $4,640 20-inch AMG wheels with which our test car was equipped.

Other performance notables on the ML550 include the Airmatic Semi-Active Air Suspension with Adaptive Damping System, which, in addition to automatically adjusting the suspension damping to the ride conditions, enables drivers to select one of three suspension settings: auto, comfort, and sport. Using a scientific, made-for-SUV testing methodology, we found there to be a significant difference between sport and comfort: in sport mode, we were unable to drink our (very full) cup of coffee without the drink spilling out over the cup every time we hit a bump in the road.

In comfort mode, this problem was significantly reduced, and we managed to get through our double mochaccino without it going cold. Mercedes-Benz engineers will no doubt be happy to know that all those thousands of hours of R&D did not go to waste. Like all modern Mercedes SUVs, the ML550 comes with the 4Matic all-wheel drive system, which ensures a 50-50 split between the front and rear wheels. And for those few who want to take it off the road, a button on the central console recalibrates the traction system, brakes, and transmission for optimal schlepping.

Despite having one of the most advanced drivetrains on the market, the ML550 delivered disappointing gas mileage: in our week with the car, we covered more than 800 miles in predominantly freeway driving, observing an average fuel economy of 17.7 mpg. This figure may be in line with the EPA's 2008 estimates of 13 mpg in the city and 18 mpg on the highway, but that knowledge did little to mitigate the $160 fuel bill for our trip to LA.

In sum
The 2008 Mercedes-Benz ML550 comes with a base price of $53,175, but a barrage of options packages will add significantly to the sticker price. Our fully loaded tester included the $8,500 Premium III package (DVD navigation system, rearview camera, Sirius Satellite Radio, Harman Kardon LOGIC7 audio system, Adaptive Damping System, air suspension, and a bunch of other creature comforts); $4,640 for the 20-inch AMG wheels; $2,670 for the rear-seat entertainment system; $1,975 for leather seats; $1,540 for black leather cabin trim; $1,110 for Keyless Go; and $375 for the iPod adapter. The grand total gave our car a final price of around $75,000. Other options can push the price of the ML550 above $80,000. With that kind of money to spend, SUV shoppers could also consider the 2007 BMW X5, the 2007 Infiniti FX45, or the 2007 Audi Q7.

The Mercedes-Benz ML550 deserves the moniker of sport utility vehicle: its gutsy on-road performance and off-road credibility make it a versatile ride. It is let down, however, by some poorly integrated and expensive optional cabin technology and a less-than-economical fuel economy.