The Mercedes-Benz E 400d 4MATIC Cabriolet, produced from 2020 to 2023 as part of the A238 facelift generation, represents a compelling blend of luxury, performance, and diesel efficiency within the E-Class range. Positioned as a high-end variant, it offered open-top motoring with a powerful diesel engine and all-wheel drive capability. This model aimed to appeal to buyers seeking a sophisticated grand tourer with everyday usability, differentiating itself from the gasoline-powered E-Class Cabriolets and offering a unique proposition in the premium convertible segment.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | E-class |
| Generation | E-class Cabrio (A238, facelift 2020) |
| Type (Engine) | E 400d (330 Hp) 4MATIC 9G-TRONIC |
| Start of production | 2020 |
| End of production | 2023 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 8.4-8.7 l/100 km (28 – 27 US mpg, 33.6 – 32.5 UK mpg, 11.9 – 11.5 km/l) |
| Fuel consumption (extra urban) | 5.1-5.5 l/100 km (46.1 – 42.8 US mpg, 55.4 – 51.4 UK mpg, 19.6 – 18.2 km/l) |
| Fuel consumption (combined) | 6.3-6.7 l/100 km (37.3 – 35.1 US mpg, 44.8 – 42.2 UK mpg, 15.9 – 14.9 km/l) |
| CO2 emissions | 166-166 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 5.4 sec |
| Acceleration 0 – 62 mph | 5.4 sec |
| Acceleration 0 – 60 mph | 5.1 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | EURO 6d-ISC-FCM |
| Weight-to-power ratio | 5.9 kg/Hp, 168.4 Hp/tonne |
| Weight-to-torque ratio | 2.8 kg/Nm, 357.1 Nm/tonne |
| Power | 330 Hp |
| Power per litre | 112.8 Hp/l |
| Torque | 700 Nm @ 1200-3200 rpm (516.29 lb.-ft. @ 1200-3200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 656 D 29 SCR |
| Engine displacement | 2925 cm3 (178.49 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Engine oil capacity | 7.5 l (7.93 US qt | 6.6 UK qt) |
| Kerb Weight | 1960 kg (4321.06 lbs.) |
| Max. weight | 2545 kg (5610.76 lbs.) |
| Max load | 585 kg (1289.7 lbs.) |
| Trunk (boot) space – minimum | 310 l (10.95 cu. ft.) |
| Trunk (boot) space – maximum | 385 l (13.6 cu. ft.) |
| Fuel tank capacity | 50 l (13.21 US gal | 11 UK gal) |
| Permitted trailer load with brakes (12%) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Length | 4835 mm (190.35 in.) |
| Width | 1860 mm (73.23 in.) |
| Width including mirrors | 2055 mm (80.91 in.) |
| Height | 1430 mm (56.3 in.) |
| Wheelbase | 2873 mm (113.11 in.) |
| Front track | 1605 mm (63.19 in.) |
| Rear (Back) track | 1609 mm (63.35 in.) |
| Front overhang | 850 mm (33.46 in.) |
| Rear overhang | 1112 mm (43.78 in.) |
| Ride height (ground clearance) | 98 mm (3.86 in.) |
| Approach angle | 12.8° |
| Departure angle | 14.4° |
| 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 brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
Powertrain & Engine Architecture
The E 400d Cabriolet is powered by the OM 656 D 29 SCR, a 2.9-liter inline-six cylinder diesel engine. This engine is a significant departure from the older V6 diesels used in previous E-Class generations, representing a move towards modular engine designs within the Mercedes-Benz portfolio. The OM 656 features a steel piston, a variable-geometry turbocharger, and a common-rail direct injection system operating at pressures up to 2,700 bar. This high-pressure injection contributes to efficient combustion and reduced emissions. The engine also incorporates a close-coupled Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) technology to meet stringent Euro 6d-ISC-FCM emission standards. 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 designed to optimize fuel efficiency and provide responsive acceleration. 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 combination of the 330 hp diesel engine and the 9G-TRONIC transmission delivers a refined and effortless driving experience. The engine’s substantial 700 Nm (516 lb-ft) of torque, available from a low 1200 rpm, provides strong acceleration in virtually any gear. The 0-60 mph sprint takes approximately 5.1 seconds, making it a genuinely quick convertible. While not as overtly sporty as some of its gasoline-powered counterparts, the E 400d offers a more relaxed and composed character, ideal for long-distance cruising. The 9G-TRONIC transmission contributes to this smoothness, with gear changes being almost imperceptible. Compared to the E 300 Cabriolet, the E 400d provides a noticeable increase in performance, particularly in mid-range acceleration. The 4MATIC system ensures confident handling, even on wet or slippery surfaces.
Equipment & Trim Levels
The E 400d 4MATIC Cabriolet typically came well-equipped as a higher-end trim. Standard features included leather upholstery, heated and ventilated front seats, a premium sound system, and a comprehensive suite of driver-assistance systems such as adaptive cruise control, lane-keeping assist, and automatic emergency braking. The A238 facelift introduced updated infotainment systems with larger screens and improved connectivity features. Optional extras included air suspension (AIRMATIC), a head-up display, and various interior trim options. The convertible top was a multi-layer acoustic soft top, designed to provide a quiet and comfortable cabin experience even at high speeds.
Chassis & Braking
The E-Class Cabriolet utilizes a sophisticated chassis design featuring a four-link front suspension and a multi-link rear suspension. The suspension is tuned to provide a balance between comfort and handling. The E 400d typically featured larger brakes compared to lower-trim models, with ventilated discs at all four corners. The electronic stability program (ESP) and anti-lock braking system (ABS) are standard features, enhancing safety and control. The steering system is a direct-steer system, providing precise and responsive steering feel.
Market Reception & Comparison
The E 400d Cabriolet was generally well-received by automotive critics, who praised its powerful engine, refined ride, and luxurious interior. The diesel engine offered a compelling alternative to gasoline engines, providing excellent fuel economy without sacrificing performance. Compared to the E 300 Cabriolet, the E 400d commanded a higher price but offered a significant performance upgrade. Its fuel economy figures of around 37.3-35.1 US mpg combined were competitive for a vehicle in its class. Some reviewers noted that the diesel engine could be slightly noisier than gasoline alternatives, but this was generally considered a minor drawback.
Legacy
The OM 656 engine has proven to be a robust and reliable powerplant, and the E 400d Cabriolet is expected to hold its value well in the used car market. The combination of luxury, performance, and efficiency makes it an attractive option for buyers seeking a premium convertible. The 9G-TRONIC transmission has also demonstrated good long-term reliability. As with any used vehicle, regular maintenance and adherence to recommended service intervals are crucial for ensuring continued reliability. The E 400d Cabriolet represents a refined and capable grand tourer, offering a unique blend of attributes within the Mercedes-Benz E-Class range.
