The Mercedes-Benz CLS 300d 4MATIC, produced from 2021 to 2023, represents a significant iteration of the CLS-Class coupe (C257 facelift). This variant combines a 2.0-liter turbocharged diesel engine with mild hybrid technology, a 9-speed automatic transmission (9G-TRONIC), and Mercedes-Benz’s 4MATIC all-wheel-drive system. Positioned as a mid-range offering within the CLS lineup, it aimed to deliver a balance of performance, efficiency, and luxury. The CLS, originally introduced in 2004, pioneered the four-door coupe segment, and the C257 generation, with its 2021 facelift, continued to refine this formula with updated styling, technology, and powertrain options.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | CLS |
| Generation | CLS coupe (C257, facelift 2021) |
| Type | CLS 300d (265 Hp) Mild Hybrid 4MATIC 9G-TRONIC |
| Start of production | 2021 |
| End of production | 2023 |
| Powertrain Architecture | MHEV (Mild Hybrid Electric Vehicle) |
| Body type | Coupe |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 7.2-7.6 l/100 km (32.7 – 30.9 US mpg) |
| Fuel consumption (extra urban) | 4.5-4.8 l/100 km (52.3 – 49 US mpg) |
| Fuel consumption (combined) | 5.5-5.8 l/100 km (42.8 – 40.6 US mpg) |
| CO2 emissions | 144-153 g/km |
| Fuel Type | Diesel |
| Acceleration 0-100 km/h | 6.4 sec |
| Acceleration 0-60 mph | 6.1 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 6D-ISC-FCM |
| Weight-to-power ratio | 7 kg/Hp |
| Weight-to-torque ratio | 3.4 kg/Nm |
| Gross battery capacity | 0.9 kWh |
| Battery voltage | 48 V |
| Battery technology | Lithium-ion (Li-Ion) |
| Electric motor power | 20 Hp |
| Electric motor Torque | 200 Nm (147.51 lb.-ft.) |
| Power | 265 Hp |
| Torque | 550 Nm (405.66 lb.-ft.) |
| Engine displacement | 1993 cm3 (121.62 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Kerb Weight | 1860 kg (4100.6 lbs.) |
| Max. weight | 2550 kg (5621.79 lbs.) |
| Trunk (boot) space (minimum) | 520 l (18.36 cu. ft.) |
| Fuel tank capacity | 50 l (13.21 US gal) |
| Number of gears | 9 |
| Gearbox type | Automatic (9G-TRONIC) |
| Length | 4988 mm (196.38 in.) |
| Width | 1890 mm (74.41 in.) |
| Height | 1435 mm (56.5 in.) |
Powertrain & Engine Architecture
The heart of the CLS 300d 4MATIC is the OM 654 M, a 2.0-liter inline-four cylinder diesel engine. This engine utilizes a sophisticated bi-turbocharger system with variable geometry turbines, enhancing both low-end responsiveness and high-end power delivery. The engine employs a common-rail direct fuel injection system operating at extremely high pressures (typically exceeding 2,700 bar) for optimized combustion. A key feature is the NANOSLIDE cylinder coating, reducing friction and wear. The mild hybrid system, utilizing a 48-volt electrical architecture, integrates a belt-driven starter-generator. This system allows for functions like extended coasting with the engine switched off, regenerative braking to recover energy, and a smoother start/stop operation. The 9G-TRONIC automatic transmission, a nine-speed unit, is known for its wide gear ratio spread, contributing to both fuel efficiency and refined cruising. It features a torque converter lockup clutch that engages across multiple gears to minimize slippage and improve efficiency.
Driving Characteristics
The CLS 300d 4MATIC delivers a refined and comfortable driving experience. While not overtly sporty, the 265 horsepower and 550 Nm (405.66 lb-ft) of torque provide ample power for confident overtaking and effortless cruising. The 9G-TRONIC transmission shifts smoothly and intelligently, selecting the appropriate gear for the driving conditions. The 4MATIC all-wheel-drive system provides excellent traction in various weather conditions, enhancing stability and control. Compared to higher-performance CLS variants like the CLS 53 AMG, the 300d prioritizes fuel economy and relaxed cruising over outright acceleration. The gear ratios are tuned for efficiency, with taller gearing in higher gears to reduce engine RPM at highway speeds. The mild hybrid system further enhances efficiency by allowing for engine-off coasting and assisting during acceleration.
Equipment & Trim Levels
The CLS 300d 4MATIC typically came well-equipped as standard. Interior features included premium upholstery (often leather or Artico leather), a multi-function steering wheel, ambient lighting, and a high-resolution infotainment system with Mercedes-Benz’s MBUX interface. Standard safety features included automatic emergency braking, lane keeping assist, and adaptive cruise control. Optional extras included a panoramic sunroof, upgraded sound systems (Burmester), ventilated and massaging seats, and a head-up display. Trim levels often varied by market, but generally offered packages that bundled popular options together. The interior design emphasized a modern and luxurious aesthetic, with flowing lines and high-quality materials.
Chassis & Braking
The CLS 300d 4MATIC utilizes an independent multi-link suspension system at both the front and rear axles. This configuration provides a comfortable ride quality while maintaining good handling characteristics. The suspension is tuned to prioritize comfort over outright sportiness, but still offers a secure and planted feel. Braking duties are handled by ventilated disc brakes on all four wheels. The braking system is equipped with ABS (Anti-lock Braking System), Electronic Stability Program (ESP), and Brake Assist. The steering system is a speed-sensitive electric power steering system, providing light and precise steering feel.
Market Reception & Comparison
The CLS 300d 4MATIC was generally well-received by automotive critics. It was praised for its refined engine, comfortable ride, and luxurious interior. Fuel economy was a particular strength, making it an attractive option for drivers seeking a stylish and efficient coupe. Compared to other CLS variants, the 300d offered a more affordable entry point into the CLS range. Against competitors like the Audi A7 and BMW 8 Series Gran Coupe, the CLS 300d 4MATIC held its own in terms of luxury, technology, and driving experience. Some critics noted that the 2.0-liter diesel engine, while capable, lacked the outright performance of larger engines offered in competing models.
Legacy
The OM 654 engine family, used in the CLS 300d 4MATIC, has proven to be a reliable and durable powertrain. The mild hybrid system adds a layer of complexity, but has also demonstrated good long-term reliability. On the used car market, the CLS 300d 4MATIC represents a compelling value proposition, offering a luxurious and well-equipped coupe at a relatively affordable price point. Maintenance costs are generally reasonable, although diesel-specific maintenance items (such as diesel particulate filter maintenance) should be considered. The C257 CLS, and specifically the 300d variant, continues to be a desirable option for buyers seeking a stylish and sophisticated four-door coupe.
