The Mercedes-Benz GLS 450d 4MATIC, introduced with the facelift of the X167 generation in September 2023, represents a significant offering in the luxury SUV segment. Positioned as a mid-to-upper trim level within the GLS range, it combines a powerful diesel engine with mild hybrid technology and a sophisticated all-wheel-drive system. This variant aims to deliver a balance of performance, efficiency, and refinement, catering to buyers seeking a spacious, capable, and technologically advanced SUV. The X167 GLS, as a whole, serves as the flagship SUV for Mercedes-Benz, offering three-row seating and a commanding presence.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | GLS |
| Generation | GLS (X167, facelift 2023) |
| Type | GLS 450d (367 Hp) Mild Hybrid 4MATIC 9G-TRONIC |
| Start of production | September, 2023 |
| Powertrain Architecture | MHEV (Mild Hybrid Electric Vehicle) |
| Body type | SUV |
| Seats | 7 |
| Doors | 5 |
| Combined fuel consumption (WLTP) | 8-9.1 l/100 km (29.4 – 25.8 US mpg, 35.3 – 31 UK mpg, 12.5 – 11 km/l) |
| CO2 emissions (WLTP) | 219-240 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 6.1 sec |
| Acceleration 0 – 62 mph | 6.1 sec |
| Acceleration 0 – 60 mph | 5.8 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6e |
| Weight-to-power ratio | 6.9 kg/Hp, 144.5 Hp/tonne |
| Weight-to-torque ratio | 3.4 kg/Nm, 295.3 Nm/tonne |
| Battery voltage | 48 V |
| Battery technology | Lithium-ion (Li-Ion) |
| Electric motor power | 20 Hp |
| Electric motor Torque | 200 Nm (147.51 lb.-ft.) |
| Electric motor location | Between the combustion engine and the transmission |
| Power | 367 Hp @ 4000 rpm |
| Torque | 750 Nm @ 1350-2800 rpm (553.17 lb.-ft. @ 1350-2800 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 656.830 |
| Engine displacement | 2989 cm3 (182.4 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Compression ratio | 15.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | BiTurbo, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 8.5 l (8.98 US qt | 7.48 UK qt) |
| Coolant | 17.2 l (18.18 US qt | 15.13 UK qt) |
| Kerb Weight | 2540 kg (5599.74 lbs.) |
| Max. weight | 3300 kg (7275.25 lbs.) |
| Max load | 760 kg (1675.51 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) |
| AdBlue tank | 31.6 l (8.35 US gal | 6.95 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 | 5209 mm (205.08 in.) |
| Width | 1956 mm (77.01 in.) |
| Width including mirrors | 2157 mm (84.92 in.) |
| Height | 1828-1928 mm (71.97 – 75.91 in.) |
| Wheelbase | 3135 mm (123.43 in.) |
| Front track | 1669 mm (65.71 in.) |
| Rear (Back) track | 1692 mm (66.61 in.) |
| Front overhang | 938 mm (36.93 in.) |
| Rear overhang | 1136 mm (44.72 in.) |
| Ride height (ground clearance) | 175-290 mm (6.89 – 11.42 in.) |
| Minimum turning circle (turning diameter) | 12.54 m (41.14 ft.) |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Number of gears and type of gearbox | 9 gears, automatic transmission G-TRONIC |
INTRODUCTION
The GLS 450d 4MATIC, part of the X167 GLS facelift launched in 2023, builds upon the foundation of Mercedes-Benz’s largest SUV. The X167 generation, introduced in 2019, aimed to provide a more luxurious and technologically advanced alternative to rivals like the BMW X7 and Audi Q7. The facelift brought updated styling, enhanced technology, and refinements to the powertrain options. The 450d variant specifically targets buyers who prioritize fuel efficiency and strong torque delivery without sacrificing the overall luxury and space offered by the GLS. It slots in between the entry-level GLS 450 and the performance-oriented GLS 580, offering a compelling balance of attributes.
Powertrain & Engine Architecture
At the heart of the GLS 450d lies the OM 656.830, a 3.0-liter inline-six cylinder diesel engine. This engine is a cornerstone of Mercedes-Benz’s modern diesel lineup, known for its efficiency and refinement. The OM 656 features a steel piston design, a stepped combustion process, and a two-stage turbocharging system (bi-turbo) with an intercooler. This configuration allows for both strong low-end torque and high-end power. The engine utilizes a commonrail direct fuel injection system operating at extremely high pressures to optimize combustion. The mild hybrid system, integrated into the powertrain, employs a 48-volt electrical architecture and a belt-driven starter-generator. This system allows for features like extended start-stop operation, regenerative braking, and a small power boost during acceleration. The engine is paired with Mercedes-Benz’s 9G-TRONIC nine-speed automatic transmission, known for its smooth shifts and wide gear ratio spread. The transmission is specifically tuned to complement the diesel engine’s torque characteristics.
Driving Characteristics
The GLS 450d delivers a driving experience characterized by effortless power and smooth refinement. The 750 Nm (553 lb-ft) of torque, available from a low 1350 rpm, provides strong acceleration in everyday driving situations and makes overtaking easy. While not as overtly sporty as the GLS 580, the 450d offers a 0-60 mph time of around 5.8 seconds, which is more than adequate for a vehicle of its size and weight. The 9G-TRONIC transmission contributes to a relaxed cruising experience, with well-spaced gear ratios that keep the engine operating efficiently. The mild hybrid system provides a subtle but noticeable boost during acceleration, enhancing responsiveness. The air suspension, standard on the GLS, provides a comfortable ride, absorbing bumps and imperfections in the road effectively. The 4MATIC all-wheel-drive system ensures confident handling in various weather conditions.
Equipment & Trim Levels
The GLS 450d typically comes well-equipped with standard features including Mercedes-Benz’s MBUX infotainment system with a large touchscreen display, leather upholstery, heated and ventilated front seats, a panoramic sunroof, and a premium sound system. Standard safety features include automatic emergency braking, lane keeping assist, and adaptive cruise control. Optional extras include massaging seats, a rear-seat entertainment system, and various interior trim options. The interior design emphasizes luxury and spaciousness, with high-quality materials and meticulous attention to detail. The third-row seating is relatively spacious for a vehicle in this class, making it suitable for families.
Chassis & Braking
The GLS 450d utilizes a sophisticated chassis design featuring an independent multi-link suspension at all four corners, coupled with the aforementioned air suspension system. This setup provides a comfortable ride and good handling characteristics. The air suspension allows for adjustable ride height, which can be useful for off-road driving or for easier entry and exit. The braking system consists of ventilated discs on all four wheels, providing ample stopping power. Anti-lock braking system (ABS), electronic stability control (ESC), and brake assist are standard features.
Market Reception & Comparison
The GLS 450d has been generally well-received by automotive critics, praised for its refined powertrain, spacious interior, and luxurious features. Compared to the gasoline-powered GLS 450, the 450d offers significantly better fuel economy, making it a more attractive option for buyers who prioritize efficiency. While the GLS 580 provides more outright performance, the 450d offers a more balanced combination of power, efficiency, and refinement. Reliability reports suggest that the OM 656 diesel engine is generally robust, although regular maintenance is crucial for long-term durability.
Legacy
The OM 656 engine family, including the version found in the GLS 450d, is expected to remain a mainstay in Mercedes-Benz’s lineup for the foreseeable future. Its combination of efficiency, power, and refinement makes it a compelling choice for buyers seeking a diesel-powered luxury SUV. The X167 GLS, as a whole, has established itself as a benchmark in the luxury SUV segment, and the 450d variant offers a particularly appealing option for those seeking a balance of attributes. On the used car market, well-maintained GLS 450d models are likely to hold their value due to their desirable combination of features and reputation for reliability.
