The Mercedes-Benz C 350 CDI BlueEFFICIENCY, produced from 2011 to 2014 as part of the W204 facelift generation, represented a compelling blend of performance and efficiency within the C-Class lineup. Positioned as a mid-to-upper tier offering, it catered to buyers seeking a refined diesel experience with substantial power and torque. This variant utilized a 3.0-liter V6 turbodiesel engine paired with the 7G-TRONIC PLUS seven-speed automatic transmission, offering a sophisticated driving experience and appealing to those prioritizing comfort and long-distance cruising. It was a key model in the European market, where diesel engines held significant popularity, and also saw moderate sales in other regions.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | C-class |
| Generation | C-class (W204, facelift 2011) |
| Type (Engine) | C 350 CDI BlueEFFICIENCY V6 (265 Hp) 7G-TRONIC PLUS |
| Start of production | 2011 |
| End of production | 2014 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 7.2 l/100 km (32.7 US mpg) |
| Fuel consumption (extra urban) | 5.2-5.3 l/100 km (45.2 – 44.4 US mpg) |
| Fuel consumption (combined) | 5.9-6 l/100 km (39.9 – 39.2 US mpg) |
| CO2 emissions | 154-157 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 6 sec |
| Acceleration 0 – 62 mph | 6 sec |
| Acceleration 0 – 60 mph | 5.7 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 6.2 kg/Hp |
| Weight-to-torque ratio | 2.6 kg/Nm |
| Power | 265 Hp @ 3800 rpm |
| Torque | 620 Nm @ 1600-2400 rpm (457.29 lb.-ft.) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 642.834 |
| Engine displacement | 2987 cm3 (182.28 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 83 mm (3.27 in.) |
| Piston Stroke | 92 mm (3.62 in.) |
| Compression ratio | 15.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Kerb Weight | 1630 kg (3593.53 lbs.) |
| Max. weight | 2220 kg (4894.26 lbs.) |
| Max load | 590 kg (1300.73 lbs.) |
| Trunk (boot) space | 475 l (16.77 cu. ft.) |
| Fuel tank capacity | 66 l (17.44 US gal | 14.52 UK gal) |
| Length | 4591 mm (180.75 in.) |
| Width | 1770 mm (69.69 in.) |
| Height | 1447 mm (56.97 in.) |
| Wheelbase | 2760 mm (108.66 in.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 7 |
| Gearbox type | automatic transmission G-TRONIC PLUS |
Powertrain & Engine Architecture
The heart of the C 350 CDI BlueEFFICIENCY is the OM 642.834 3.0-liter V6 diesel engine. This engine is a robust and well-regarded design, known for its durability and smooth operation. It features a common rail direct injection system, delivering fuel at extremely high pressures for optimized combustion. The engine utilizes a variable geometry turbocharger (VGT) and an intercooler to maximize power and efficiency. The VGT adjusts the turbine vanes to optimize airflow across the engine’s operating range, improving both low-end torque and high-end power. The 7G-TRONIC PLUS transmission is a seven-speed automatic gearbox that provides smooth and responsive shifts. It features a torque converter lock-up clutch that engages at higher speeds to improve fuel efficiency. The transmission also includes a manual shift mode, allowing drivers to select gears for more control.
Driving Characteristics
The C 350 CDI BlueEFFICIENCY delivers a refined and effortless driving experience. The 620 Nm (457 lb-ft) of torque available from just 1600 rpm provides strong acceleration in virtually any gear. The 0-60 mph sprint takes approximately 5.7 seconds, making it a surprisingly quick sedan. Compared to the C 220 CDI or C 250 CDI models, the C 350 CDI offers significantly more power and a more relaxed cruising experience. While not as sporty as the C 350 gasoline variant, the diesel provides a broader, more usable powerband. The 7G-TRONIC PLUS transmission contributes to the smooth and seamless power delivery, making it ideal for long highway journeys.
Equipment & Trim Levels
The C 350 CDI BlueEFFICIENCY typically came well-equipped, reflecting its position in the C-Class range. Standard features often included leather upholstery, automatic climate control, a multi-function steering wheel, and a high-quality audio system. Optional extras included a navigation system, a panoramic sunroof, adaptive cruise control, and parking assist. The “BlueEFFICIENCY” designation indicated the inclusion of fuel-saving technologies such as start-stop functionality and optimized aerodynamics. Interior trim options varied, with choices in wood veneers and aluminum accents available.
Chassis & Braking
The W204 C-Class features a sophisticated chassis design. The front suspension utilizes a McPherson strut setup, while the rear employs a multi-link independent suspension. This configuration provides a good balance between ride comfort and handling precision. The C 350 CDI typically came equipped with ventilated disc brakes on all four wheels, providing ample stopping power. Anti-lock braking system (ABS) and electronic stability control (ESP) were standard safety features. The suspension tuning was generally geared towards comfort, but the car still offered a reasonably engaging driving experience.
Market Reception & Comparison
The C 350 CDI BlueEFFICIENCY was generally well-received by automotive critics. It was praised for its powerful and efficient engine, smooth transmission, and comfortable ride. Compared to its gasoline-powered counterparts, the C 350 CDI offered significantly better fuel economy. However, some critics noted that the diesel engine was slightly noisier than the gasoline engines. In terms of reliability, the OM 642 engine proved to be quite durable, although regular maintenance was essential. Compared to other diesel-powered competitors like the BMW 330d and Audi A4 3.0 TDI, the C 350 CDI offered a competitive combination of performance, luxury, and fuel efficiency.
Legacy
The Mercedes-Benz C 350 CDI BlueEFFICIENCY remains a popular choice in the used car market. The OM 642 engine is known for its longevity, and with proper maintenance, these cars can provide many years of reliable service. However, potential buyers should be aware of the potential for diesel particulate filter (DPF) issues, particularly if the car has been primarily used for short trips. Overall, the C 350 CDI BlueEFFICIENCY represents a well-engineered and refined diesel sedan that continues to offer a compelling value proposition for those seeking a comfortable and efficient luxury car.
