2018 Mercedes-Benz GLS-Class GLS 63 AMG

The 2018 GLS-Class is Mercedes-Benz's flagship SUV. It's available with three engines, a twin-turbo V6 (362 horsepower, 369 pound-feet of torque) in the GLS 450; a twin-turbo V8 (449 hp, 516 lb-ft) in the GLS 550; and an even more powerful V8 (577 hp, 561 lb-ft) in the barnstorming GLS 63 AMG variant. The GLS 450 and GLS 550 are equipped with a nine-speed automatic transmission, while the GLS 63 AMG comes with a seven-speed automatic. All GLS models feature Mercedes-Benz's all-wheel-drive system called 4Matic.

Still, outright performance is not what the GLS is about. Rather, the GLS is designed to accommodate passengers and cargo with features such as second-row seats with adjustable recline. And, in a pinch, seats can be stowed and moved for flexible cargo requirements. With optional features, all of this can be done electronically at the touch of a button.

Thanks to its street-oriented suspension, the GLS rides smoothly over the road, giving drivers and passengers one of the most serene experiences in its class. And yet an available body roll control system and sport-oriented suspension can firm up the handling.

Some buyers may hesitate once they see the price, particularly if it's a well-equipped example. And others may find the size and dynamics too big and too soft, respectively. But the GLS is levels above the cutthroat midsize SUV and crossover market, and it dominates in the full-size segment by bringing an S-class to the SUV fight.

Notably, we picked the 2018 Mercedes-Benz GLS-Class as one of Edmunds' Best Luxury SUVs for this year.

The 2018 Mercedes-Benz GLS-Class is a seven-passenger, large luxury SUV that's offered in three models. The GLS 450 is the base model that's well equipped but doesn't include many of the higher-end features you might expect in an luxury SUV. The GLS 550, ups the power and includes many features that are optional on the GLS 450. Finally, performance aficionados will be drawn to the ultra-powerful AMG GLS 63. All three feature standard all-wheel drive.

The GLS 450 comes with a turbocharged V6 engine (362 hp, 369 lb-ft), 19-inch alloy wheels, a self-leveling air suspension, power-folding and auto-dimming side mirrors, LED running lights and taillights, roof rails, a power liftgate and Mbrace Connect remote vehicle access (via smartphone app; includes remote start).

Interior highlights include premium vinyl upholstery, heated front seats, a 10-way power driver seat (with four-way power lumbar adjustment), 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. Technology 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.

An available Premium package 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 lane keeping assist and blind-spot monitoring.

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-speaker Harman 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 GLS 550 starts with all of the above as standard, but it uses a twin-turbo V8 engine (449 hp, 516 lb-ft). It also adds 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 both the GLS 450 and GLS 550 include a panoramic sunroof, heated second-row seats, diamond-quilted leather upholstery and the Driver Assistance package, which adds adaptive cruise control, lane keeping assist, blind-spot monitoring, and front and rear collision mitigation. Also available is 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 and adds an even more powerful turbocharged V8 (577 hp, 561 lb-ft), 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 and a flat-bottom sport steering wheel.

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