The 2020 Mercedes-Benz GLS is better than you think off road

There are vehicles that can go off road, and then there are off-road vehicles. The former put an emphasis on daily, on-road manners, focusing on comfort and convenience above all. The latter, meanwhile, prioritize all-terrain prowess, often compromising things like ride quality and efficiency in the process.

Mercedes-Benz, however, believes you can have both.

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That's why I'm out in Big Dune, Nevada, just north of Las Vegas, riding right-seat in a 2020 Mercedes-Benz GLS580 prototype. No, Mercedes is not positioning the new GLS as a hard-core off-roader -- that's what the G-Class is for. Instead, Mercedes wants to prove that it can offer drivers a wonderfully comfortable experience, whether the GLS' tires are crossing sand or pavement.

When it launches later this year, Mercedes' flagship SUV will be available with a 3.0-liter, turbocharged, six-cylinder engine in GLS450 guise. But for the sake of this prototype ride-along, I'm in the GLS580, which gets a brand-new, 4.0-liter, twin-turbocharged V8, complete with Mercedes' EQ-Boost mild-hybrid tech. This big brute puts out 483 horsepower and 516 pound-feet of torque, and all-wheel drive is standard.

The 48-volt EQ-Boost engine is important for two reasons. First, it provides an extra 21 horsepower and 184 pound-feet of torque for short bursts of acceleration. But it also powers the E-Active Body Control system which works in conjunction with the air suspension, controlling the spring and damper rates at each wheel individually. The GLS can scan the road ahead, be it dirt or pavement, to prime the suspension for any upcoming irregularities. The result is a remarkably flat ride no matter the road surface, no sway bars needed.

Andreas Zygan, chief development engineer for Mercedes-Benz SUVs, first takes me out in a GLS not equipped with the E-ABC tech. Running over dirt whoops at around 15 mph, the GLS standard suspension does an acceptable job of smoothing out the ride, but the front and rear ends dip and dive with every undulation.

Switching to a GLS equipped with E-ABC, I can feel an immediate difference. And following the non-E-ABC car, I can see how it bounces along the road. My car, meanwhile, is smooth as silk and totally composed. It's really quite remarkable.

Then there's E-ABC's party trick: Free Driving Assist. To demonstrate, Zygan intentionally buries the GLS' wheels in some soft sand. Then he just presses a button and the GLS starts bouncing up and down. Keeping the car in gear, and with gentle pressure on the throttle, the big SUV rocks itself free. It's a neat trick, but Mercedes reminds me this is an assistance program. If you find yourself buried up past the axle, you may still have to dig your way out.

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The GLS580 will be offered with an optional, two-speed transfer case and three selectable ride heights for a maximum ground clearance of 11 inches. There are no differential lockers, however -- instead, the GLS utilizes a multi-plate clutch with torque on demand. This system can send anywhere from 0 to 100 percent of the engine's torque to the front or rear axles. This means you can have almost all the benefits of diff lockers without the punishment of wheel hop or steering wheel kickback while going around tight turns.

With its huge power and serious capability, the GLS580 roosts through Big Dune, throwing up massive amounts of sand. From the right seat, I can see Zygan burying his foot in the throttle, whipping the steering wheel from lock to lock. The GLS seems totally at home in this environment.

No, the GLS is never going to square off with purpose-built off-roaders, but with its E-ABC tech and off-road drive programming, it looks to be the most capable Mercedes SUV short of the G-Class. Hopefully I'll still feel the same after getting my own turn behind the wheel in the coming months.