The Mercedes-Benz GLS 63 AMG, specifically the X167 generation produced from March 2020 to September 2023, represents the pinnacle of performance within the full-size GLS SUV lineup. Positioned as the flagship model, it combines luxurious accommodations for up to seven passengers with the potent power of a hand-built AMG V8 engine enhanced by EQ Boost mild-hybrid technology. This variant caters to buyers seeking uncompromising performance and prestige in a large SUV package, competing with rivals like the BMW X7 M50i and the Range Rover Sport SV.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | GLS |
| Generation | GLS (X167) |
| Type | AMG GLS 63 V8 (612 Hp) EQ Boost 4MATIC+ TCT |
| Start of production | March, 2020 |
| End of production | September, 2023 |
| Powertrain Architecture | MHEV (Mild Hybrid Electric Vehicle) |
| Body type | SUV |
| Seats | 7 |
| Doors | 5 |
| Fuel consumption at Low speed (WLTP) | 12.6 l/100 km (18.7 US mpg, 22.4 UK mpg, 7.9 km/l) |
| Fuel consumption at very high speed (WLTP) | 13 l/100 km (18.1 US mpg, 21.7 UK mpg, 7.7 km/l) |
| CO2 emissions (WLTP) | 287-295 g/km |
| Fuel consumption (economy) – urban (NEDC, WLTP equivalent) | 15.4 l/100 km (15.3 US mpg, 18.3 UK mpg, 6.5 km/l) |
| Fuel consumption (economy) – extra urban (NEDC, WLTP equivalent) | 10 l/100 km (23.5 US mpg, 28.2 UK mpg, 10 km/l) |
| Fuel consumption (economy) – combined (NEDC, WLTP equivalent) | 11.9-12 l/100 km (19.8 – 19.6 US mpg, 23.7 – 23.5 UK mpg, 8.4 – 8.3 km/l) |
| CO2 emissions (NEDC, WLTP equivalent) | 273 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 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6d ISC-FCM |
| Weight-to-power ratio | 4.2 kg/Hp, 239.5 Hp/tonne |
| Weight-to-torque ratio | 3 kg/Nm, 332.7 Nm/tonne |
| Gross battery capacity | 0.9 kWh |
| Battery voltage | 48 V |
| Battery technology | Lithium-ion (Li-Ion) |
| Electric motor power | 22 Hp |
| Electric motor Torque | 250 Nm (184.39 lb.-ft.) |
| Engine Power | 612 Hp @ 5750-6500 rpm |
| Engine Torque | 850 Nm @ 2500-4500 rpm (626.93 lb.-ft. @ 2500-4500 rpm) |
| 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.) |
| 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) |
| Kerb Weight | 2555 kg (5632.81 lbs.) |
| Max. weight | 3395 kg (7484.69 lbs.) |
| Max load | 840 kg (1851.88 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) |
| Permitted trailer load with brakes (12%) | 3500 kg (7716.18 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Wheelbase | 3135 mm (123.43 in.) |
| Gearbox | 9 gears, automatic transmission TCT AMG SPEEDSHIFT |
| Front brakes | Ventilated discs, 400 mm |
| Rear brakes | Ventilated discs, 370 mm |
| Front tires | 275/50 R21 |
| Rear tires | 315/45 R21 |
Powertrain & Engine Architecture
At the heart of the GLS 63 AMG lies the M177 4.0-liter twin-turbocharged V8 engine. This engine, hand-assembled in Affalterbach, Germany, produces 612 horsepower at 5750-6500 rpm and a massive 850 Nm (626.93 lb-ft) of torque between 2500-4500 rpm. The engine utilizes direct fuel injection and features a hot-side-inside turbocharger configuration for improved responsiveness. Adding to this is the 48V EQ Boost system, which incorporates a belt-driven starter-generator. This system provides an additional 22 horsepower and 250 Nm of torque, enabling features like smoother auto start/stop operation, energy recovery, and a slight performance boost during acceleration. The transmission is a 9-speed TCT AMG SPEEDSHIFT automatic, known for its quick and precise shifts. Power is distributed to all four wheels via the 4MATIC+ all-wheel-drive system, which allows for fully variable torque distribution between the front and rear axles.
Driving Characteristics
The GLS 63 AMG delivers a driving experience that belies its substantial size. Acceleration is remarkably swift, achieving 0-60 mph in around 4 seconds. The EQ Boost system provides instant torque fill, minimizing turbo lag and contributing to a responsive feel. The AMG-tuned suspension, featuring adaptive air suspension, provides a comfortable ride while maintaining excellent body control. The 9-speed transmission offers smooth and quick gear changes, and the driver can select various driving modes (Comfort, Sport, Sport+, Individual) to tailor the vehicle’s behavior to their preferences. Compared to lower-powered GLS variants, the 63 AMG offers a significantly more engaging and dynamic driving experience, sacrificing some fuel economy for exhilarating performance.
Equipment & Trim Levels
The GLS 63 AMG comes standard with a comprehensive array of luxury and technology features. Interior appointments include premium leather upholstery, heated and ventilated front and rear seats, a panoramic sunroof, and a Burmester surround sound system. Standard driver-assistance systems include adaptive cruise control, lane-keeping assist, and automatic emergency braking. Optional extras include massaging seats, rear-seat entertainment systems, and a head-up display. The interior design emphasizes luxury and sophistication, with AMG-specific styling cues such as a sport steering wheel and unique trim options.
Chassis & Braking
The GLS 63 AMG features a robust chassis designed to handle the engine’s immense power. The suspension utilizes AMG Ride Control air suspension with adaptive damping, allowing for adjustable ride height and stiffness. Large ventilated disc brakes (400mm front, 370mm rear) provide ample stopping power. The braking system is further enhanced by ABS, electronic brake-force distribution, and brake assist. The 4MATIC+ all-wheel-drive system ensures optimal traction in all conditions. The vehicle’s weight is managed through the use of lightweight materials in certain components, contributing to its agility.
Market Reception & Comparison
The GLS 63 AMG was generally well-received by automotive critics, praised for its powerful engine, luxurious interior, and surprisingly agile handling for a vehicle of its size. However, its high price tag and relatively poor fuel economy were noted as drawbacks. Compared to other GLS variants, the 63 AMG offers a significantly more engaging driving experience but comes at a substantial premium. Against competitors like the BMW X7 M50i and Range Rover Sport SV, the GLS 63 AMG holds its own in terms of performance and luxury, offering a unique blend of attributes that appeal to discerning buyers.
Legacy
The X167 GLS 63 AMG represents a high point in the evolution of the high-performance luxury SUV. While long-term reliability data is still emerging, the M177 engine has proven to be generally robust in other AMG applications. On the used car market, these models command a premium due to their performance and exclusivity. The combination of a powerful V8 engine, advanced technology, and luxurious appointments ensures that the GLS 63 AMG will remain a desirable vehicle for years to come.
