Unlike anything else on, off road: Mercedes G550

Few vehicles have traveled a stranger road than the G-Class. Originally designed in 1979 as a military, utility vehicle, the Mercedes G-Class has transformed over the decades into a luxury class SUV.

Created with impressive, off-road capability, the vast majority now are unlikely to confront anything more challenging than a speed bump in a country club parking lot. The combination of old school SUV with layers of added luxury gives the G-Class a unique personality.

Buried just below the surface of the G550 are its military roots. Beneath the boxy body is a stout, ladder frame, with solid axles and impressive angles of approach/departure (36 and 27 degrees, respectively). The full-time, 4×4 system has low range gearing and locking, electrically controlled front, center and rear differentials. Electronic stability control comes along for the ride. It adds up to a very robust (5,578 pounds), highly capable SUV.

Given its lofty price at $113,000, rare is the G-Class that sets a tire off-road intentionally. On road, the G-Class feels like what it is — a big, truck-based SUV. The tall body exhibits some lean while cornering, and steering feel is stiff. Ride quality is firm, but comfortable. The G550’s high profile is subject to wind buffeting on the highway.

Though the G-Class is 33 years old, the powertrain has certainly kept up with the times. A 5.5-liter engine is paired with a seven-speed automatic transmission. The Benz V-8 makes 388 horsepower and 391 lb.-ft. of torque, and that’s enough motivation to usher the G-Class from 0-to-60 mph in an estimated 6.0 seconds — quite quick, for a 2-ton vehicle.

The engine feels strong at all rpm levels and has a muscle car’s exhaust tone. The top speed is electronically limited at 125 mph, which is all the more impressive, given the G550’s brick-like aerodynamics. Published tests show the G-Class stopping from 60 mph in under 130 feet, which is strong performance from a vehicle this size. Towing capacity is strong at up to 7,000 pounds.

Fuel economy is weak. EPA estimates are 12 mpg city, 15 mpg highway, and I averaged 13 mpg overall. That said, gas mileage is not likely to be any more of a concern for the average G-Class shopper than it would be for an exotic sports car buyer. Mercedes is once again offering a higher performance variation for 2013. The G63 AMG packs a twin turbocharged version of the 5.0-liter V-8. Rated at 544 hp and 560 lb.-ft. of torque, the company estimates that it will take 5.3 seconds to get from 0-to-60 mph.

The G-Class stands 6-foot, 4-inch tall, and it’s a long step up into the cabin. Running boards are provided to assist passage, though they’re too narrow to be useful for the large or wide of foot. So tight is the cabin seal that you have to swing any door like you mean it, to shut it.

Once inside, leg room up front runs short is you’re taller than 6 feet tall, however, there’s sufficient leg room in back for 6 footers. Headroom is almost limitless, and would stand up to anything, up to and including a revival of top hats or beehive hairdos.

Initially spartan, the G-Class interior has been outfitted over the years with luxury and technology features. Climate controls are located very low on the center stack. The lone cupholder on my tester was attached to the side of this stack. The absence of parking spots for beverages is surprising in this segment, and a reminder that the G-Class was designed years before our national fascination with cups on the go.

Cargo capacity ranges from 45.2-79.5 cubic feet. Lift-over height is low — surprisingly so, given the vehicle’s height. Wheel wells keep the load floor from being totally flat. The house-sized windows afford good visibility, though the straight back view is hindered by the trio of rear seat headrests.

The interior is well appointed, as you might expect. The leather upholstered seats are heated and ventilated, and the roster of standard equipment includes a harmon/kardon sound system, Bluetooth connectivity, a navigation system with 7-inch screen, a 40GB hard drive and a rearview camera. A blind spot system alerts the driver to vehicles lurking alongside.

Extreme utility and extreme luxury are rarely found in the same vehicle. It’s this marriage of opposites that’s at the heart of the G550’s personality. Behind the downright upright styling is a mixture of rugged and refined, unlike anything else on the road.