2023 Mercedes-AMG GLS 63

The price of a 2023 Mercedes-AMG GLS 63 is just shy of $140k, and for that sort of money, you have a right to expect something out of the ordinary. Sitting at the apex of the GLS range, the AMG GLS 63 is a study in excess, playing the dual roles of a large luxury three-row SUV and performances car, courtesy of a fearsome 603-horsepower twin-turbocharged V8 engine. Making enormous three-ton seven-seaters go absurdly fast is rather unnecessary, but it's certainly popular and a number of rival manufacturers will sell you the same sort of thing. From Europe, the similarly priced 630-hp BMW Alpina XB7 comes to mind. But even pricier and more powerful is the 682-hp Cadillac Escalade-V, born and bred right here in the USA. All these heavyweights employ eight cylinders and boosted induction to produce big numbers, but how does the GLS 63 fare in this company? Let the battle of the ballistic bruisers begin.

The 2023 AMG GLS 63 elbows its way into 2023 unchanged from last year, except for the starting price of the brawny SUV, which increases by $3,600.

The MSRP for a new Mercedes-AMG GLS 63 is $139,000 this year, excluding the $1,150 destination charge. There's only one trim level to choose from, so what features you get and what you end up paying for it will depend on how you spec it. Luckily, it comes with a comprehensive list of standard features, including heated and ventilated front seats, a panoramic sunroof, five-zone climate control, a 13-speaker Burmester audio system, and an entire suite of driver assists.

Extra-cost cosmetic enhancements such as blacked-out exterior trim via the AMG Night package are up to you, as is the second-row Executive Rear Seat package for transporting two rear-seat passengers in the utmost comfort. If it were ours, we'd leave it as is, except for adding heating for the steering wheel (a standalone option), plus heated first- and second-row armrests and rapid heating for the front seats via the Warmth & Comfort package. Specced like this, it will cost you under $142k, all-in.

The interior of the AMG GLS 63 is fully in keeping with its price tag, and top-quality materials abound. There's Nappa leather on the seats and wood accents on the dashboard, with the impressive dual-display MBUX infotainment system sitting atop four rectangular vents with separate climate controls below them. Said climate control is a five-zone system, with the third row getting its own zone. Everything is electrically adjustable, from the front seats to the steering wheel, the latter being a Nappa leather-trimmed multifunction item festooned with buttons and controls. Even the rear seats fold on their own power. There's plenty of space inside the GLS, too, at least up to the second row, with the third row suitable for people of shorter stature or children.

Interior space is plentiful in the GLS, and the first two rows have enough head- and legroom for even the tallest adults to stretch out. The third row isn't bad at all, but more suitable for shorter people or children, as is a standard issue with three-row SUVs. It's roomier than an X7 in the last row, though, and there's more headroom than a Range Rover here, but the Escalade still has the biggest third row of all of them. The second-row bench can be swapped out for a dual Executive Rear Seat arrangement that reduces seating capacity to six and installs second-row captain's chairs with heating, ventilation, and massaging functions.

Even with all three rows of seats in use, there is a perfectly acceptable 17.4 cu-ft of trunk space left over - as big as the trunk of a large luxury sedan. The third row folds down electrically in about five seconds, increasing the trunk volume to 48.7 cu-ft. The second row also folds electrically, and with these seats also stowed away, maximum utility space reaches 84.7 cu-ft. The cargo bay features floor-mounted tie-downs, a grocery-bag hook, and side parcel nets. The rear air suspension can lower the car by almost two inches via a button in the trunk to reduce the lift-over height.

Cabin stowage is good, with big door pockets in all four doors, a glove compartment, two heated and cooled cupholders in the front center console with a wireless charging pad in front of them, and a roomy lidded storage box behind them. The second and third rows get their own cupholders, and if you spec the Executive Rear Seat second-row package, a wireless charging pad is part of the deal, while the cupholders for this row are heated and cooled as well.

There aren't too many interior colors and materials to choose from, the default seat covering being Exclusive Nappa leather in either black or Tartufo/black. Black or Macchiato Beige/black with diamond stitching is the only other option for $250.

There are three available no-cost wood options for interior accents, Grey Linden Wood being the standard, and Natural Grain Grey Oak or Brown Walnut Wood being options. There's also Aluminum with Longitudinal Grain that is a free choice, too. The other options will require buyers to pay more - Manufaktur Natural Grain Black Flamed Ash Wood or Brown Linden "Flowing Lines" Wood ($850), Metal Weave ($600), or AMG Carbon Fiber ($1,750).

The dashtop, steering wheel, and upper door trims are covered in Nappa leather as well, while the roofliner is in black microfiber faux suede. Red seatbelts can be had for $300, a microfiber-trimmed AMG Performance steering wheel costs $600, and carbon fiber accents are an additional $300.

This being the top-of-the-range GLS, standard features are comprehensive, with soft-closing doors, a power liftgate, keyless entry and go, a power panoramic sunroof, heated, massaging, and ventilated power front seats, heated second-row seats, power-folding second- and third-row seats, heated and cooled front cupholders, five-zone climate control, and a garage-door opener all included. Optional extras include heated third-row seats, an air purifier, and a heated steering wheel.

The MBUX infotainment system comes with dual 12.3-inch displays - one a digital gauge cluster and the other an adjacent touchscreen - and the system incorporates tech such as "Hey, Mercedes" keyword activation, voice control, navigation, multiple USB-C ports, Bluetooth audio streaming, Android Auto, Apple CarPlay, SiriusXM, HD Radio, and a 13-speaker Burmester audio system. The system can be operated via the touchscreen or a center-console-mounted touchpad controller. You can order MBUX Augmented Video for the navigation system for $350, add the MBUX Interior Assistant for $250, or spec a 26-speaker Burmester audio system for $4,550.

The engine in the Mercedes-AMG GLS 63 is a twin-turbocharged 4.0-liter V8 hand-built by AMG and producing 603 hp and 627 lb-ft of torque. The drivetrain comprises an AMG Speedshift nine-speed automatic transmission that sends power to all four wheels via the standard AMG Performance 4Matic+ AWD system. But forget about the RWD mode some of the AMG sedans have; this one is permanently all-wheel drive. Trailering is a strong suit, too, despite the performance focus, and the big SUV has a 7,700-pound tow rating. Given the surfeit of power, performance is riveting, and the Mercedes-AMG GLS 63's 0-60 sprint is dispatched in a rapid 4.1 seconds on its way to a top speed of 174 mph.

Power delivery is sharp, thanks to the responsive tuning of the TCT nine-speed transmission, the torque-filling ability of the 48V mild-hybrid system, and the sheer level of power on tap. It storms off the line with no time wasted to wheelspin, thanks to the 4Matic+ system's all-wheel-drive grip. Downshifts can feel a little aggressive, but it suits an AMG, though it still can't match the brilliant eight-speed ZF transmission in rival brands for overall smoothness and responsiveness. Large three-row SUVs aren't meant to be flung around, so the GLS 63's driving experience is a bit of a compromise in order to give it a sporting bent. It really hangs on, with high grip limits giving it a very secure cornering stance that will give several sporty sedans a fright. Still, you can feel the physics at work, and there is a teetering quality to the whole business, like charging about the garden with a wheelbarrow full of bricks. All the electronic systems keep you on the straight and narrow, and it's devastatingly effective for a big, tall car. The ride is a bit firm, too, especially on the 23s, but it stops short of becoming punishing.

Despite the mild-hybrid system, the Mercedes-AMG GLS 63's mpg figures don't make for impressive reading - not an unexpected result for a large gas-guzzling SUV. Gas mileage is rather poor, with EPA estimates of 14/19/16 mpg for the city/highway/combined cycles. While that combined figure is 1 mpg worse than that of the Alpina XB7, it's a lot better than the hideously thirsty Escalade V's 13 mpg.

With its fuel capacity being a generous 23.8 gallons, the GLS 63 can still offer you a range of just over 380 miles on a tank.

Being a large and expensive luxury SUV, there is, of course, no NHTSA or IIHS safety review of the Mercedes-AMG GLS 63. But given its suite of active and passive safety features, it should be just as safe as any modern Mercedes. It has the obligatory ABS, stability control, tire-pressure monitoring, and a rear-view camera, along with seven airbags, but we're a bit disappointed that second-row side airbags come only with the optional $3,700 Executive Rear Seat package.

Driver assists are comprehensive, with the GLS 63 fitted as standard with forward-collision warning, automatic braking initiation, driver-alertness monitoring, active and evasive steering assist, blind-spot monitoring, lane-departure warning, lane-keep and lane-change assist, adaptive cruise control with stop & go, Mercedes' pre-safe system, a surround-view camera, automatic LED headlights with automatic high beams, rain-sensing wipers, three auto-dimming rearview mirrors, parking sensors front and rear, and automatic parking. Heated Magic Vision Control wiper blades cost $350.

According to JD Power, the Mercedes-AMG GLS 63's reliability rating is middling, with the GLS lineup's quality and reliability metric garnering just 75 out of 100. Compare that to the significantly better score of 83 handed to the Cadillac Escalade. The GLS's recall history isn't stellar either, with the 2021 GLS suffering no fewer than ten recalls. The 2022 GLS was recalled seven times for issues ranging from a loose steering coupling and seatback lock failure to a disabled eCall system and an unsecured ground connection bolt. Some 2022 recalls also apply to the 2023 model year, these being recalls to address a failing fuel pump that may cause a lack of drive power and rear-door window-trim bars that may detach.

The limited warranty of the Mercedes-AMG GLS 63 is valid for four years/50,000 miles, and the same period and mileage apply to the powertrain warranty.

From the outside, the GLS 63 is clearly an AMG product, with a huge Panamericana grille with vertical chromed slats, a trio of gaping air intakes in the lower bumper, and 21-inch AMG ten-spoke alloy wheels. A variety of larger wheels up to 23 inches in size can be specified at extra cost. The standard 21-inch wheels look a little small on what is a very large car with a 206.4-inch length and 123.4-inch wheelbase. The roof rails and glasshouse surround are picked out in satin silver, but these can be blacked out as part of the AMG Night package, along with the front valance, rear apron, and mirror caps. At the rear, quad exhausts peer from underneath the bumper.

As needless as rapid seven-seaters tend to be, the GLS 63 is great fun. Sure, it's niche entertainment, but to each their own. The ride isn't pillowy soft, but it's not punishing either, and handling is secure but hardly the last word in sportiness - SUVs don't handle like sports cars, and trying to make them inevitably results in a compromised product. We feel the BMW Alpina XB7 is possibly less compromised, while it's also quicker. The Escalade V is the best at proper SUV things, with excellent ride and handling and the biggest third row - if you can live with the terrible fuel economy. As we said, these cars are compromises, and the GLS 63 isn't necessarily the best compromise of the lot, although it's the cheaper option among those mentioned here.