2017 Mercedes-Benz GLS550 4Matic First Drive Review

Before it was renamed the GLS for the upcoming model year, the Mercedes-Benz GL received high praise as the winner of our 2013Motor TrendSport/Utility of the Year award. "There is nothing more you could want or need in an SUV," former road test editor Scott Mortara said at the time. We lauded the model for its smooth ride, royal interior, and balanced dynamics, particularly in the diesel 350d. But have we reached the pinnacle of civilization? Is there room for further improvement?

For 2017, the refreshed full-size SUV features a variety of upgrades. Along with a redesigned interior, the model receives a retuned air suspension and a larger, standalone 8-inch COMAND screen. Also new is a nine-speed automatic transmission that is standard on the GLS 350d, GLS450, and GLS550. The midrange GLS550 features 449 hp, or 20 more hp than its predecessor. The GLS 63, meanwhile, ups the ante to 577 hp, 27 hp more than the previous model. Drivers can select up to six transmission modes, including Comfort, Slippery, and Sport; Individual, Off-Road, and Off-Road + are available on most models for further customization.

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Other than these changes, the GLS represents a pretty conservative update from the GL. Vestiges from its predecessor remain, including the phone dial pad and hodgepodge of buttons cluttering the center console. Like we criticized in our recent large luxury SUV comparison, Mercedes' full-size SUV still feels a bit dated on the inside. That's of course with the exception of plush Nappa leather seats with diamond quilting.

With the GL already leading the competition in U.S. sales, perhaps Mercedes didn't need to make any huge changes. When you think of large luxury SUVs, the first thought in your mind is probably an Escalade. But more buyers here are clamoring for the current GL than the standard-wheelbase Escalade, Infiniti QX80, and Audi Q7 so far this year.

To see if the GLS retains its former charms, Mercedes challenged us to drive it in the Austrian Alps one afternoon. Driving the GLS500 (or the GLS550 in the U.S. market) it wasn't long before we realized that the new transmission modes really come into play. Slippery mode provides plenty of traction on wet surfaces, although its lack of power delivery makes it hard to pass other traffic. Once you kick things up to Sport mode, the GLS immediately jumps into action to unleash a marvelous amount of power. In either driving mode, however, the GLS suffers from a light, somewhat detached steering feel. The nine-speed transmission seemed to do its duty without much jerking, although we'd need to conduct further testing before issuing a verdict. The GLS500 feels most at home in snow. Although you can go with Slippery mode, it's also confident enough to tackle snow in Comfort. If you drive too exuberantly, electronic nannies quickly come to the rescue while still making you feel like you're having a little fun.

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Mercedes estimates the V-8-powered GLS model can hit 0-62 mph in 5.3 seconds. If true, Mercedes can pat itself on the back. We tested a 2015 Escalade at 5.9 seconds to 60 mph and an Infiniti QX80 at 6.3 seconds. During our 2013 Sport/Utility of the Year testing, the Mercedes GL550 hit 60 in 5.1 seconds, so the GLS is likely even faster than advertised. Most buyers should also be satisfied with the 362-hp, 3.0-liter V-6 GL450. When we tested the GL450 earlier this year, it came in at a respectable 6.2 seconds to 60.

Mercedes has long called its full-size utility offering "the S-Class among SUVs." We wouldn't object to the statement, but we'd add to it. Not only does it offer supreme luxury, a quiet cabin, and a highly composed ride, but it has also further proven its cred off the beaten path.

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