Mercedes-AMG GLS63 4MATIC

Thanks to consistent expansion of its offerings, Mercedes-Benz’s lineup has become somewhat confusing over the last decade or so. In the commendable effort to insert a modicum of logic, Daimler has renamed its SUV models (among others) to align them with the sedans that form the core of the brand's portfolio. The most fortunate beneficiary of this renaming scheme is undoubtedly the new GLS, the face-lifted and tweaked successor to the GL-class. Its model designation puts it squarely on a level with the S-class, despite the fact that it uses a stretched version of the architecture under the M-class—er, GLE-class.

Once conceived as a replacement for the venerable G-wagen, Daimler now calls the GLS "the S-class among SUVs." And to back it up, the massive seven-seater receives more power and equipment than ever. The GLS350d is fitted with a brawny 3.0-liter V-6 turbo-diesel that makes 255 horsepower—15 more than before—and 455 lb-ft of torque. The GLS450 carries over its 3.0-liter twin-turbocharged V-6 gasoline engine, rated at 362 horsepower and 369 lb-ft of torque, so the times when the “450” moniker denoted a value-priced V-8 are well and truly over. The GLS550 and its 4.7-liter twin-turbo V-8 is up by 20 horsepower to a full 449, while the AMG-fettled GLS63—now officially named the Mercedes-AMG GLS63—makes 577 horsepower, 27 more than before.

Somewhat curiously, however, the GLS63 AMG sticks with Mercedes-Benz’s twin-turbocharged 5.5-liter V-8, an engine that has been replaced by a twin-turbo 4.0-liter V-8 elsewhere. And it keeps the AMG-specific seven-speed automatic, while the three other models are now fitted with a nine-speed automatic. Needless to say, the ultrapowerful and fast AMG version is our favorite, although the other engines are impressive, too, particularly the efficient diesel.

In the update for 2017, Mercedes upgraded the GLS’s adjustable chassis modes. As before, there are Comfort and Sport modes, Individual allows the driver to choose bespoke settings, and Off-Road helps the GLS conquer rough terrain. The AMG model adds a Sport+ setting, while non-AMGs can get the optional Off-Road Engineering package—it adds a low-range transfer case and locking center-differential lock—adds a further Off-Road+ mode. Oh, and if you really want to get specific, there’s also a Slippery setting for when the roads are, well, slippery.

The "S-class among SUVs" could be topped only by the Maybach of SUVs, and we hear that just such a vehicle is a distinct possibility. We predict the GLS will continue to fare well in its competitive set, which includes the Lexus GX and LX models, the Infiniti QX80, the Range Rover, and the Cadillac Escalade. And in Maybach trim, it could hold its own against the Bentley Bentayga and the upcoming SUV by Rolls-Royce. Orders commence in December, and the first adopters will receive their SUVs in late March.Stylistically, the GLS is set apart from its predecessor with a redesigned front end. That means swoopier headlights and a massive, SL-inspired grille with “wings” so large that they themselves have stylized air intakes. The profile view remains unchanged, while the rear end gets redesigned taillights and revised chrome trim. Inside, the dashboard is upgraded with a larger central screen, a change that mirrors that of the GLE. Indeed, the driver's view in both cars is virtually identical, including the three-spoke steering wheel that would look more at home in a sporty A-class than in this 202-inch-long behemoth.