The Mercedes-Benz CLS 400d 4MATIC, produced from 2021 to 2023 as part of the C257 facelift generation, represents a compelling blend of luxury, performance, and efficiency within the four-door coupe segment. This variant, equipped with a potent diesel engine and all-wheel drive, aimed to deliver a refined driving experience while maintaining respectable fuel economy. It occupied a mid-to-high position within the CLS lineup, offering a step up in performance from the lower-powered models while remaining more accessible than the AMG variants. The C257 generation, introduced in 2018 and facelifted in 2021, built upon the success of the original CLS, further refining its design and incorporating the latest Mercedes-Benz technology.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | CLS |
| Generation | CLS coupe (C257, facelift 2021) |
| Type (Engine) | CLS 400d (330 Hp) 4MATIC 9G-TRONIC |
| Start of production | 2021 |
| End of production | 2023 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – urban (NEDC) | 8.2-8.6 l/100 km (28.7 – 27.4 US mpg, 34.4 – 32.8 UK mpg, 12.2 – 11.6 km/l) |
| Fuel consumption (economy) – extra urban (NEDC) | 5-5.3 l/100 km (47 – 44.4 US mpg, 56.5 – 53.3 UK mpg, 20 – 18.9 km/l) |
| Fuel consumption (economy) – combined (NEDC) | 6.2-6.5 l/100 km (37.9 – 36.2 US mpg, 45.6 – 43.5 UK mpg, 16.1 – 15.4 km/l) |
| CO2 emissions (NEDC) | 163-172 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 5.2 sec |
| Acceleration 0 – 62 mph | 5.2 sec |
| Acceleration 0 – 60 mph | 4.9 sec |
| Maximum speed | 250 km/h (155.34 mph), Electronically limited |
| Emission standard | Euro 6D-ISC-FCM |
| Weight-to-power ratio | 5.6 kg/Hp, 177.4 Hp/tonne |
| Weight-to-torque ratio | 2.7 kg/Nm, 376.3 Nm/tonne |
| Power | 330 Hp @ 3600-4000 rpm |
| Power per litre | 112.8 Hp/l |
| Torque | 700 Nm @ 1200-3000 rpm (516.29 lb.-ft. @ 1200-3000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 656.929 |
| Engine displacement | 2925 cm3 (178.49 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 82 mm (3.23 in.) |
| Piston Stroke | 92.3 mm (3.63 in.) |
| Compression ratio | 15.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | BiTurbo, Intercooler |
| Valvetrain | DOHC, CAMTRONIC |
| Engine oil capacity | 7.5 l (7.93 US qt | 6.6 UK qt) |
| Kerb Weight | 1860 kg (4100.6 lbs.) |
| Max. weight | 2545 kg (5610.76 lbs.) |
| Max load | 685 kg (1510.17 lbs.) |
| Trunk (boot) space – minimum | 520 l (18.36 cu. ft.) |
| Fuel tank capacity | 50 l (13.21 US gal | 11 UK gal) |
| AdBlue tank | 23.5 l (6.21 US gal | 5.17 UK gal) |
| Max. roof load | 100 kg (220.46 lbs.) |
| Permitted trailer load with brakes (12%) | 1900 kg (4188.78 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Permitted towbar download | 76 kg (167.55 lbs.) |
| Length | 4988 mm (196.38 in.) |
| Width | 1890 mm (74.41 in.) |
| Width including mirrors | 2069 mm (81.46 in.) |
| Height | 1435 mm (56.5 in.) |
| Wheelbase | 2939 mm (115.71 in.) |
| Front track | 1620 mm (63.78 in.) |
| Rear (Back) track | 1618 mm (63.7 in.) |
| Front overhang | 888 mm (34.96 in.) |
| Rear overhang | 1161 mm (45.71 in.) |
| Drag coefficient (Cd) | 0.28 |
| Minimum turning circle (turning diameter) | 11.9 m (39.04 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives permanently the four wheels of the vehicle. |
| Drive wheel | All wheel drive (4×4) |
| Number of gears and type of gearbox | 9 gears, automatic transmission G-TRONIC |
| Front suspension | Independent multi-link suspension |
| Rear suspension | Independent multi-link suspension |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | Front wheel tires: 245/45 R18; 245/40 R19; 245/35 R20Rear wheel tires: 275/40 R18; 275/35 R19; 275/30 R20 |
| Wheel rims size | Front wheel rims: 8J x 18; 8J x 19; 8J x 20Rear wheel rims: 9J x 18; 9J x 19; 9J x 20 |
Powertrain & Engine Architecture
The heart of the CLS 400d 4MATIC is the OM 656.929, a 2.9-liter inline-six cylinder diesel engine. This engine represents a significant advancement in Mercedes-Benz diesel technology, featuring a two-stage turbocharging system with a variable turbine geometry (VTG) turbocharger and an additional exhaust gas turbocharger. This configuration delivers both strong low-end torque and high power output. The engine utilizes a common-rail direct injection system operating at extremely high pressures (2700 bar) for optimized combustion and reduced emissions. The CAMTRONIC valve lift adjustment system on both intake and exhaust valves further enhances efficiency and responsiveness. Paired with the engine is the 9G-TRONIC nine-speed automatic transmission, known for its smooth shifts and wide gear ratio spread. This transmission is crucial for maximizing fuel efficiency and providing comfortable cruising at highway speeds. The 4MATIC all-wheel-drive system distributes power between the front and rear axles, enhancing traction and stability in various driving conditions.
Driving Characteristics
The CLS 400d 4MATIC delivers a refined and effortless driving experience. The substantial 700 Nm (516 lb-ft) of torque available from just 1200 rpm provides strong acceleration in virtually any gear. The 0-60 mph sprint takes approximately 4.9 seconds, making it a genuinely quick vehicle. The 9G-TRONIC transmission contributes to this performance with its quick and seamless gear changes. Compared to the CLS 300d, the 400d offers a noticeable increase in power and torque, resulting in more confident overtaking and a more relaxed driving experience, especially when fully loaded. While not as overtly sporty as the AMG variants, the 400d provides ample power for spirited driving. The all-wheel-drive system inspires confidence in inclement weather, providing excellent grip and stability.
Equipment & Trim Levels
The CLS 400d 4MATIC typically came well-equipped as standard. Features included Mercedes-Benz’s MBUX infotainment system with a large touchscreen display, leather upholstery, heated front seats, automatic climate control, and a comprehensive suite of safety features such as adaptive cruise control, lane keeping assist, and automatic emergency braking. Optional extras included a premium Burmester sound system, a panoramic sunroof, ventilated front seats, and various interior trim options. The interior design emphasized luxury and sophistication, with high-quality materials and meticulous attention to detail. The standard dashboard configuration featured dual 12.3-inch displays, one for the instrument cluster and one for the infotainment system.
Chassis & Braking
The CLS 400d 4MATIC features an independent multi-link suspension at both the front and rear axles, providing a comfortable and controlled ride. The suspension is tuned to prioritize comfort, but still offers good body control in corners. Ventilated disc brakes are fitted on all four wheels, providing ample stopping power. The electronic stability program (ESP) and anti-lock braking system (ABS) work in conjunction to enhance safety and stability. The steering is electrically assisted, offering precise and responsive control.
Market Reception & Comparison
The CLS 400d 4MATIC was generally well-received by automotive critics. It was praised for its refined engine, comfortable ride, and luxurious interior. The fuel economy was also considered impressive for a vehicle of its size and performance. Compared to the CLS 300d, the 400d offered a significant performance upgrade, justifying the higher price tag for those seeking more power. However, some critics noted that the CLS, even in 400d guise, wasn’t as engaging to drive as some of its rivals, such as the BMW 8 Series Gran Coupe or the Audi A7. Reliability reports have been generally positive, with the OM 656 engine proving to be a robust and durable unit.
Legacy
The CLS 400d 4MATIC represents a high point in Mercedes-Benz’s diesel technology. The OM 656 engine is known for its efficiency, refinement, and longevity. On the used car market, these models hold their value relatively well, particularly those with low mileage and a full service history. The combination of luxury, performance, and fuel economy makes the CLS 400d 4MATIC a desirable option for buyers seeking a sophisticated and capable four-door coupe. Its advanced technology and comfortable driving experience ensure it remains a competitive vehicle in the luxury car segment.
