Plans to add a new high-performance AMG variant to its GL Class lineup has been one of Mercedes-Benz’s worst kept secrets, with prototypes for the potent full-size luxury SUV spotted testing in public for over two years now. Today the covers have come off the 2013 Mercedes-Benz GL63 AMG, which is confirmed to hit showrooms in the first quarter of next year.

Based on the recently revealed 2013 GL Class, the new GL63 AMG dons the usual assortment of visual enhancements from the stylists at AMG. This includes a slightly more aggressive front bumper featuring enlarged air intakes, unique daytime running lights, chrome detailing and pumped fenders. The GL63 AMG also picks up a set of 21-inch light alloy wheels shod with 295/40 tires, “V8 BITURBO” badging and illuminated door sills with an aluminum finish. At the rear is a quartet of exhaust tips finished in chrome.

While the visual enhancements may only be noticed by true AMG fans, there’s nothing subtle about the car’s powerplant. Under the hood is the Affalterbach tuner’s latest twin-turbocharged 5.5-liter V-8 engine that delivers a peak output of 550 horsepower and 560 pound-feet of torque in the GL63 AMG. That’s the same output you get in the 2012 ML63 AMG but it’s a fraction higher than the output of the 2013 G63 AMG and quite the leap over the 429 horsepower and 516 pound feet of torque of the GL550.

Mercedes-Benz promises 0-60 mph acceleration in just 4.9 seconds and an electronically-limited top speed of 155 mph, numbers that are simply astonishing for a vehicle of this size. Remember, the GL, even in high-performance AMG trim, can seat seven.

Ensuring the vehicle stays maneuverable, even at speed, are a host of electronic systems including AMG RIDE CONTROL sports suspension with AIRMATIC as well as the ACTIVE CURVE SYSTEM. The entire setup consists of air suspension, sports struts, an automatic self-leveling function, active dampers, and active anti-roll bars both front and rear. The driver can control all of these features by switching between two suspension modes, “Comfort” and “Sport”. Also aiding handling performance is 4MATIC all-wheel drive, electronic traction and stability control, and electronic steering.

The only transmission is the familiar AMG SPEEDSHIFT seven-speed automatic, which itself has a trio of modes to choose from including sport (S), manual (M) and controlled efficiency (C). The latter helps save fuel by relying on an engine stop-start system, a decoupling feature for cruising, a milder throttle and early shift times. The standard brakes are ventilated and perforated discs at all four corners--15.4 x 1.4 inches (front) and 13.6 x 1.0 inches (rear).

Open up the doors and you're treated with a plush interior lined with leather trim for the seats and MB-Tex used on the dashboard, armrests and door trim. The steering wheel is an AMG design that features four spokes as well as a flattened bottom and aluminum shift paddles. Standard goodies include stainless steel pedals, AMG floor mats, a parking assistant, Mercedes’ COMAND interface with Bluetooth and USB connectivity and tri-zone automatic climate control. Some optional extras worthy of mentioning include a 360-degree camera monitoring system, lane keeping and blind spot assist systems, a panoramic glass roof and a Bang & Olufsen premium sound system.

Full pricing details and gas mileage for the 2013 Mercedes-Benz GL63 AMG will be announced closer to next year’s launch.


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