Used 2017 Mercedes-Benz GLS-Class GLS 450 4MATIC® SUV Review

The 2017 Mercedes-Benz GLS-Class SUV has a new name, and we're here to tell you why. The S-Class, you see, has been Mercedes' flagship sedan for decades; it's a luxury icon in its own right. Mercedes wanted its top-of-the-line family crossover to tap into that heritage, so last year's GL-Class has become this year's GLS-Class. The idea is that it's the S-Class of SUVs, and we have to admit that this well-mannered beast makes a pretty compelling case.

Freshened front-end styling helps differentiate the 2017 GLS-Class from its GL-Class forebear.

The GL-Class was already at the top of its game, but the 2017 GLS still manages to take things up a notch. Mild styling changes front and rear mask more significant upgrades under the skin, including a superb new nine-speed automatic transmission (on all models except the AMG) and an upgraded infotainment system with a larger central display and a touchpad. The GLS is great to drive, too, with remarkable agility for such a behemoth and powerful acceleration in every trim.

Direct competition for the 2017 GLS-Class is surprisingly thin. BMW doesn't offer a full-size three-row crossover yet, and the otherwise stellarAudi Q7 lacks the Benz's range of engines and adult-friendly third-row seat. The Land Rover LR4 boasts inimitable style and serious off-road capability along with true three-row seating, but it's really a class down from the ultra-luxurious GLS. Japanese rivals include the distinctive Infiniti QX80 and the aging but still competent Lexus LX 570, while the gargantuan Cadillac Escalade and Lincoln Navigator serve as patriotic alternatives. But for now, at least, no large crossover or SUV can match the all-around talents of the 2017 Mercedes-Benz GLS-Class.

Standard safety features on the 2017 Mercedes-Benz GLS include automatic crosswind stabilization, trailer stability assist, front side airbags, a driver knee airbag, full-length side curtain airbags, a forward collision mitigation system with automatic braking and a driver attention/drowsiness monitor. Also standard are a rearview camera and a five-year subscription to Mbrace Connect (includes Mercedes-Benz roadside assistance).

For additional peace of mind, Mbrace Secure is available and includes automatic collision notification, stolen-vehicle location and more. The Premium 1 package adds a blind-spot monitor and lane keeping assist, while the Driver Assistance package contributes adaptive cruise control, an upgraded collision mitigation system with pedestrian recognition, speed limit assist and "active" blind spot and lane keeping assist systems that can automatically guide the car back into its lane if the driver fails to heed their warnings.

The 2017 Mercedes-Benz GLS is a large, seven-passenger SUV available in three models: GLS 450, GLS 550 and AMG GLS 63.

The GLS 450 is equipped with 19-inch alloy wheels, a self-leveling air suspension, power-folding auto-dimming side mirrors, automatic headlights, LED running lights and taillights, a sunroof, automatic wipers, roof rails, rear privacy glass, a power liftgate and Mbrace Connect remote vehicle access (via smartphone app; includes remote start).

Every GLS-Class model comes with all-wheel drive and a multimode terrain selector on the center console.

Interior highlights include MB-Tex premium vinyl upholstery, heated front seats, a 10-way power driver's seat (with four-way power lumbar), driver-seat memory settings, a power-adjustable leather-wrapped steering wheel, an auto-dimming rearview mirror, genuine wood trim and dual-zone automatic climate control. Electronics highlights include the COMAND infotainment interface (with both a control knob and a touchpad), an 8-inch central display, a rearview camera, Bluetooth, a 115-volt household-style power outlet, and a sound system that features HD radio and dual USB ports.

The Premium package for these two models adds keyless entry and ignition, a power front passenger seat with memory settings, lighted door sills and multicolor ambient lighting, a navigation system with real-time traffic, voice controls, Apple CarPlay and satellite radio, as well as a couple of notable safety features (see Safety section, below).

The Lighting package bundles adaptive LED headlights and automatic high beams. The Parking Assist package adds front and rear parking sensors, an automated parallel-parking system and a surround-view camera system. Also available are three-zone automatic climate control, ventilated front seats, leather upholstery, a 13-speakerHarman Kardon sound system with a CD/DVD player, an SD card reader and "multicontour" front seats that add a massaging feature and adjustable side bolsters and shoulder supports.

The GLS550 starts with all of the above as standard, adding or substituting a V8 engine, 21-inch alloy wheels, adaptive suspension dampers, sporty exterior styling cues, soft-close doors and upgraded interior trim (including wood steering-wheel inserts). The optional Night package throws in 21-inch black wheels and gloss-black exterior accents.

Optional items on all three of the above models (GLS 450, GLS 550) include a panoramic sunroof, heated second-row seats, Designo diamond-quilted leather upholstery and the Driver Assistance package, which consists of adaptive cruise control and several advanced safety technologies (see Safety section, below). The GLS 450 and GLS 550 can also be equipped with an Off-Road package that includes an upgraded multimode terrain selector, a dual-range transfer case and front underbody protection; on the GLS 450, it also adds the GLS 550's standard adaptive dampers.

The high-performance AMG GLS 63 starts with most of the above, adding or substituting an even more powerful V8, a sport exhaust, exclusive 21-inch alloy wheels, a sport-tuned suspension, upgraded brakes, adaptive stabilizer bars (the "Active Curve System" in Mercedes-speak), AMG-specific styling elements inside and out, enhanced bolstering for the front seats, upgraded leather upholstery (with a complimentary headliner) and a flat-bottomed sport steering wheel.

All four GL models can also be outfitted with a trailer hitch, a heated steering wheel, power-sliding second-row seats for third-row access, rear side window sunshades, a rear entertainment system, a WiFi hotspot and a 14-speaker Bang & Olufsen audio system.

The 2017 Mercedes-Benz GLS 450 comes with a 3.0-liter turbocharged gasoline V6 rated at 362 hp and 369 lb-ft of torque. The GLS 550 gets a 4.6-liter V8 that churns out 449 hp and 516 lb-ft of torque. All three of these models come standard with all-wheel drive and a nine-speed automatic transmission.

The GLS550 pictured here comes standard with a turbocharged V8 engine that serves up sports-carlike acceleration.

The AMG GLS 63, meanwhile, employs a 5.5-liter V8 that provides an astonishing 577 hp and 561 lb-ft of torque. It comes with all-wheel drive and a seven-speed automatic.

According to the EPA, the GLS 450 should return 19 mpg combined (17 city/22 highway), with the GLS 550 dropping to 16 mpg combined (14 city/18 highway) and the AMG GLS 63 bringing up the rear at 14 mpg combined (13 city/17 highway).

Properly equipped, all GLS-Class models can tow a maximum of 7,500 pounds.