Given its jumbo dimensions and nearly three-ton weight, the GL-Class crossover is an odd candidate for a performance upgrade, but that hasn't stopped AMG from applying its full go-fast treatment to the 'ute.
Just what separates the GL63 from its mild-mannered, family-hauling siblings? Racy fascias front and rear along with sporty 21-inch wheels are among the changes, but the primary distinction is a twin-turbocharged 5.5-liter V8 that runs 18.8 psi of boost and produces 550 horsepower along with 560 lb-ft of torque. That's enough to enable the hopped-up mastodon to gallop from zero-to-60 mph in just 4.8 seconds.
Given the GL63's potent engine and pavement-pounding mass, fuel economy checks in at just 13 mpg in the city and 17 mpg on the highway. More impressive is towing capacity, which maxes out at 7,500 lbs.
Shifting duties are handled by a seven-speed automatic transmission that brings to the table no less than three unique driving modes.Power is put the ground via Mercedes' 4Matic all-wheel-drive system, which distributes engine power at a ratio of 40:60 to the front and rear axles and pays dividends on the drag strip as well as slushy roads.
Although the GL63 is by no means a sports car in the twisties, it's also more than a straight-line special due to handling-enhancing features like an AMG-developed sports suspension with AIRMATIC air springs, independent damper struts, automatic level control and Adaptive Damping System (ADS), which are all combined for the first time with Active Curve System, which provides active roll stabilization.
When it comes time to bring the party to a halt, the GL63 AMG is equipped with a high-performance braking system with high fade resistance, featuring ventilated and perforated brake discs at all four corners. Front discs come in at 15.4 inches, while the rear measure 13.6 inches.
Inside, the GL63 AMG improves on the standard GL's already impressive interior with well-bolstered sports seats, a three-spoke AMG steering wheel, sport pedals and numerous AMG badges. Leather upholstery and wood trim are of course standard, as are niceties such as heated/ventilated/massaging front seats, a navigation system, a panoramic sunroof and a Harmon/Kardon premium stereo system.
There's space for seven adults across three rows of seats, with even the rearmost row being a snap to access thanks to power easy-entry second-row seats. Cargo space measures 16 cubic feet behind the third-row seats; fold down the third row, and 49.4 cubic feet are available, while also stowing the second row unlocks 93.8 cubes.
Standard and Optional Features
The GL63 come standard with nearly every luxury one could imagine, including leather upholstery, genuine wood trim, heated/ventilated/massaging front sports seats, heated rear seats, a navigation system, a Harmon/Kardon AM/FM/CD stereo with AUX and USB inputs, Sirius satellite radio, HD radio, a panoramic sunroof, a power liftgate, tri-zone automatic climate control, a rearview camera, a surroundview camera system, Bluetooth connectivity with audio streaming, power folding third row seats, cruise control, auto on/off headlights, a 115-volt power outlet, LED daytime running lights and taillights, cruise control, bi-xenon headlights and 21-inch alloy wheels.
Options are limited to a rear seat entertainment system, a wood/leather steering wheel, a performance AMG steering wheel, rear sunshades, a night vision system and a Bang & Olufsen sound system.
Mercedes-Benz has long been known for its safety features, and the GL63 AMG will certainly not tarnish that reputation. In addition to ABS and ESP stability control, the SUV boasts nine supplemental restraints including two-stage front air bags, a knee air bag for the driver and pelvic air bags which work together with curtain and side air bags to provide extra protection for front occupants in dangerous side-impact collisions.
High-tech safety items include Blind Spot Assist, Lane Keeping Assist and Pre-Safe, a system that charges the brakes when it detects an impending impact in order to limit the severity of the wreck as much as possible.
Also standard is an "ATTENTION ASSIST" system that can alert the driver to the first signs of drowsiness, a factor that causes more than 100,000 accidents a year in the U.S. A steering sensor is coupled to smart software that uses 70 parameters to establish a unique driver profile during the first 20 minutes of driving. Between 50 and 112 mph, the system identifies the erratic steering corrections drivers make as they begin to get drowsy and triggers an audible warning and a "Time for a Rest?" message with a coffee cup icon in the instrument cluster.
Buyers can also order Mercedes' Collision Prevention Assist, a radar-based system that works to prevent or mitigate collisions. Between 20 and 155 mph, the system monitors the distance between the GL and the vehicle in front of it, emitting visual and acoustic warnings and priming the brakes if it senses that a collision is imminent.
As a three-row performance crossover, the GL63 AMG's only true rival is the smaller, less powerful Land Rover Range Rover Sport Supercharged. Those who need only two rows of seating can also check out the BMW X5 M and the Porsche Cayenne Turbo.