The Mercedes-Benz GLS 63, specifically the X167 facelift model introduced in September 2023, represents the pinnacle of performance within the third-generation GLS lineup. Positioned as the flagship variant, it combines the spaciousness and luxury expected of a full-size SUV with the exhilarating power of a hand-built AMG V8 engine. This iteration builds upon the foundation laid by the X167 series, which debuted in 2019, offering a refined and technologically advanced driving experience. The “63” designation signifies its status as the highest-performance model, differentiating it from the GLS 450, 580, and other trims.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | GLS |
| Generation | GLS (X167, facelift 2023) |
| Type | AMG GLS 63 V8 (612 Hp) Mild Hybrid 4MATIC+ AMG SPEEDSHIFT TCT 9G |
| Start of production | September, 2023 |
| Powertrain Architecture | MHEV (Mild Hybrid Electric Vehicle) |
| Body type | SUV |
| Seats | 7 |
| Doors | 5 |
| Combined fuel consumption (WLTP) | 13.3-13.5 l/100 km (17.7 – 17.4 US mpg, 21.2 – 20.9 UK mpg, 7.5 – 7.4 km/l) |
| CO2 emissions (WLTP) | 300-306 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 4.2 sec |
| Acceleration 0 – 62 mph | 4.2 sec |
| Acceleration 0 – 60 mph | 4.1 sec |
| Maximum speed | 250 km/h (155.34 mph), Electronically limited |
| Emission standard | Euro 6e |
| Weight-to-power ratio | 4.3 kg/Hp, 233.1 Hp/tonne |
| Weight-to-torque ratio | 3.1 kg/Nm, 323.8 Nm/tonne |
| Battery voltage | 48 V |
| Battery technology | Lithium-ion (Li-Ion) |
| Electric motor power | 22 Hp |
| Electric motor Torque | 250 Nm (184.39 lb.-ft.) |
| Electric motor location | Between the combustion engine and the transmission |
| Power | 612 Hp @ 5750-6500 rpm |
| Power per litre | 153.7 Hp/l |
| Torque | 850 Nm @ 2500-4500 rpm (626.93 lb.-ft. @ 2500-4500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 177.980 |
| Engine displacement | 3982 cm3 (243 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 83 mm (3.27 in.) |
| Piston Stroke | 92 mm (3.62 in.) |
| Compression ratio | 8.6:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | 2 x Twin-scroll turbo, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 9.5 l (10.04 US qt | 8.36 UK qt) |
| Coolant | 15.7 l (16.59 US qt | 13.81 UK qt) |
| Kerb Weight | 2625 kg (5787.13 lbs.) |
| Max. weight | 3395 kg (7484.69 lbs.) |
| Max load | 770 kg (1697.56 lbs.) |
| Trunk (boot) space – minimum | 355 l (12.54 cu. ft.) |
| Trunk (boot) space – maximum | 2400 l (84.76 cu. ft.) |
| Fuel tank capacity | 90 l (23.78 US gal | 19.8 UK gal) |
| Max. roof load | 100 kg (220.46 lbs.) |
| Permitted trailer load with brakes (12%) | 3500 kg (7716.18 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Permitted towbar download | 140 kg (308.65 lbs.) |
| Length | 5233 mm (206.02 in.) |
| Width | 2030 mm (79.92 in.) |
| Width including mirrors | 2157 mm (84.92 in.) |
| Height | 1836 mm (72.28 in.) |
| Wheelbase | 3135 mm (123.43 in.) |
| Front track | 1705 mm (67.13 in.) |
| Rear (Back) track | 1725 mm (67.91 in.) |
| Front overhang | 956 mm (37.64 in.) |
| Rear overhang | 1142 mm (44.96 in.) |
| Ride height (ground clearance) | 250 mm (9.84 in.) |
| Minimum turning circle (turning diameter) | 13.1 m (42.98 ft.) |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Number of gears and type of gearbox | 9 gears, automatic transmission AMG SPEEDSHIFT TCT |
Powertrain & Engine Architecture
At the heart of the AMG GLS 63 lies the M177.980 4.0-liter V8 engine. This engine is hand-assembled in Affalterbach, Germany, adhering to AMG’s “one man, one engine” philosophy. It features a hot-V configuration, meaning the turbochargers are located within the V of the engine, resulting in a more compact design and improved responsiveness. The engine utilizes direct fuel injection and employs two twin-scroll turbochargers to deliver a formidable 612 horsepower and 850 Nm (626.93 lb-ft) of torque. The mild-hybrid system, incorporating a 48-volt electrical architecture, adds a further 22 hp and 250 Nm (184.39 lb-ft) of torque, enhancing efficiency and providing smoother start/stop functionality. The engine is paired with the AMG SPEEDSHIFT TCT 9G automatic transmission, a nine-speed unit known for its rapid and precise shifts. This transmission is specifically tuned for performance, offering various driving modes to suit different conditions and driver preferences.
Driving Characteristics
The AMG GLS 63 delivers a driving experience that belies its size. Despite its substantial weight, the combination of the powerful V8 engine and the responsive transmission results in exhilarating acceleration – 0 to 60 mph in just 4.1 seconds. The 4MATIC+ all-wheel-drive system provides exceptional traction, ensuring confident handling in various weather conditions. The air suspension, standard on this model, offers a comfortable ride while also allowing for adjustable ride height. Compared to the GLS 450 or 580, the 63 offers a significantly more aggressive and sporty driving experience. The gear ratios are optimized for performance, prioritizing acceleration over fuel economy. While the standard GLS models emphasize luxury and comfort, the 63 is geared towards drivers who demand high performance and dynamic handling.
Equipment & Trim Levels
The AMG GLS 63 comes standard with a comprehensive suite of luxury and technology features. Interior appointments include AMG-specific sport seats upholstered in Nappa leather, a flat-bottom AMG steering wheel, and brushed aluminum pedals. The MBUX infotainment system with a large touchscreen display is standard, along with a premium Burmester surround sound system. Optional extras include a head-up display, rear-seat entertainment system, and various customization options for interior trim and exterior styling. The GLS 63 is positioned as the top-of-the-line trim, offering a level of luxury and performance not found in other GLS variants.
Chassis & Braking
The chassis of the AMG GLS 63 is specifically tuned to handle the increased power and performance. It features AMG-tuned air suspension with adaptive damping, providing a balance between comfort and control. The suspension utilizes hydro-pneumatic elements for enhanced ride quality. Braking duties are handled by high-performance ventilated discs on all four wheels, providing ample stopping power. The AMG braking system is designed to withstand the stresses of high-performance driving. Stabilizer bars are thicker than those found on lower trims, further enhancing handling stability.
Market Reception & Comparison
The AMG GLS 63 has been well-received by automotive critics, praised for its impressive performance, luxurious interior, and overall refinement. While fuel economy is not a strong point (13.3-13.5 l/100 km), it is comparable to other high-performance SUVs in its class. Compared to rivals like the BMW X7 M50i and the Porsche Cayenne Turbo, the GLS 63 offers a unique blend of luxury, space, and performance. Some critics have noted that its size can make it challenging to maneuver in tight spaces, but the advanced driver-assistance systems help mitigate this issue.
Legacy
The M177 engine family, including the version found in the GLS 63, has proven to be relatively reliable, although maintenance costs are higher than those associated with less powerful engines. The 48-volt mild-hybrid system is still relatively new, so long-term reliability remains to be fully assessed. On the used car market, the AMG GLS 63 holds its value well due to its exclusivity and performance credentials. It represents a compelling option for buyers seeking a high-performance, full-size SUV with a luxurious interior and a prestigious brand name.
