WATCH  2017 Mercedes AMG GLS63
Channel: Auto Today
Date: 2017-01-02

WATCH  2017 Mercedes AMG GLS63. Of all the car guys I pestered in my childhood, I remember only one. While most of the neighborhood gentry contentedly passed their time messing around under the hoods of tired pony cars while sipping cheap beer and cranking proto-rock from the finest sensationally titled riff vendors FM radio had to offer, Gary—maybe his real name, maybe not—had it bad for the Chevrolet Suburban. Or maybe that’s just the only vehicle he had to work with. Either way, after a summer of watching various performance components find their way onto the ’Burban, Gary took me for a ride that nullified everything I thought I knew about the relationship between speed and mass.

Fast-forward some 30 years, and I’m hustling a Mercedes-AMG GLS63 through the craggy terrain outside Moab, Utah, experiencing Technicolor flashbacks of the sort usually reserved for Woodstock survivors. Sure, the GLS63 is an eminently more refined beast, its heated and ventilated leather front buckets—with massage function, natch—and chubby, leather-covered wheel a far cry from the blanket-covered bench and oversize Hula Hoop tiller of Gary’s Suburban. But for delivering forward thrust far out of scale with an enormous SUV, the vibe is definitely there.

Adding an “S” for 2017

Refreshed and renamed for the 2017 model year, the GLS63 comes by its quickness not by an infusion of aftermarket add-ons, but by careful design and engineering from the start. As a Mercedes-AMG model, its 5.5-liter twin-turbo V-8 is hand-assembled by the skilled crew of AMG technicians in a facility in Affalterbach, Germany. While the 5.5-liter isn’t new for 2017, AMG did manage to harvest an additional 27 ponies from the engine, which now produces 577 horsepower; torque increases by 1 lb-ft, to 561, but its full brunt now comes online at 1750 rpm, slightly earlier than before. While the non-AMG 2017 GLS-class models feature a new nine-speed automatic transmission, the GLS63 retains the familiar AMG Speedshift Plus seven-speed automatic, which is tailored to play nicely with the GLS63’s rear-biased all-wheel-drive calibration. While it’s possible that this powertrain will enable the GLS63 to beat the 4.8-second time we recorded with a 2013 GL63 AMG (Mercedes quotes 4.5 seconds for the new GLS63), our test team thinks it won’t be a lot quicker. On the road, the thrust comes on early, hurling roughly 5800 pounds of AMG at the horizon with more aggression than seems necessary in polite company. Man, what a weird and wonderful world we live in.

Tasked with putting the kibosh on these proceedings, 15.4-inch front and 14.2-inch rear brake rotors supplant the GLS550’s 14.8- and 13.6-inch units (the GLS350d and GLS450 make do with comparatively puny 13.8- and 13.6-inch rotors). While brake-pedal action is far from telepathic, it’s dramatically improved over the gooey brake feel that plagued our long-term 2013 GL450. Stomp the pedal and the brakes haul this big guy down from speed without drama. Applying light pressure while carving the canyon roads that run throughout the Moab region extracts an equally composed response, which is good, as mistakes here can have grave consequences. We’re pretty sure we saw more than one burned-out Suburban rotting in the valleys below.

Like all GLS models, the GLS63 comes standard with the air-sprung Airmatic suspension, in this case recalibrated for AMG-specific duty. Selecting Sport+ mode via the console-mounted Dynamic Select control alters the damping characteristics—as well as optimizing the transmission mapping—for spirited driving. Good as it is, the suspension can’t mask the sound of 21-inch 295/40 Continental summer tires slapping across proud expansion strips or bounding through a deep crater in the road. Sound aside, the suspension does a fine job of mitigating such impacts, allowing minimal intrusion on cabin comfort.

Backsound credit by bensound.com