The Mercedes-Benz C 350 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-range offering, it slotted between the more economical C 250 models and the higher-performance C 63 AMG. This variant featured a naturally aspirated 3.5-liter V6 engine paired with the 7G-TRONIC PLUS seven-speed automatic transmission, aiming to deliver a refined driving experience with respectable power and fuel economy. The W204 C-Class, overall, was a significant model for Mercedes-Benz, solidifying its position in the competitive compact executive car segment.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | C-class |
| Generation | C-class (W204, facelift 2011) |
| Type (Engine) | C 350 BlueEFFICIENCY V6 (306 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) | 9.4-9.6 l/100 km (25 – 24.5 US mpg) |
| Fuel consumption (extra urban) | 5.3-5.6 l/100 km (44.4 – 42 US mpg) |
| Fuel consumption (combined) | 6.8-7 l/100 km (34.6 – 33.6 US mpg) |
| CO2 emissions | 159-164 g/km |
| Fuel Type | Petrol (Gasoline) |
| 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) – Electronically limited |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 5 kg/Hp |
| Weight-to-torque ratio | 4.1 kg/Nm |
| Power | 306 Hp @ 6500 rpm |
| Torque | 370 Nm @ 3500-5250 rpm (272.9 lb.-ft. @ 3500-5250 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 276.957 |
| Engine displacement | 3498 cm3 (213.46 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 92.9 mm (3.66 in.) |
| Piston Stroke | 86 mm (3.39 in.) |
| Compression ratio | 12.2:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Naturally aspirated |
| Valvetrain | DOHC |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Kerb Weight | 1535 kg (3384.1 lbs.) |
| Max. weight | 2125 kg (4684.82 lbs.) |
| Max load | 590 kg (1300.73 lbs.) |
| Trunk (boot) space (minimum) | 475 l (16.77 cu. ft.) |
| Fuel tank capacity | 66 l (17.44 US gal | 14.52 UK gal) |
| Permitted trailer load (with brakes) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load (without brakes) | 750 kg (1653.47 lbs.) |
| Length | 4591 mm (180.75 in.) |
| Width | 1770 mm (69.69 in.) |
| Width including mirrors | 2008 mm (79.06 in.) |
| Height | 1447 mm (56.97 in.) |
| Wheelbase | 2760 mm (108.66 in.) |
| Front track | 1549 mm (60.98 in.) |
| Rear track | 1552 mm (61.1 in.) |
| Front overhang | 775 mm (30.51 in.) |
| Rear overhang | 1056 mm (41.57 in.) |
| Drag coefficient (Cd) | 0.28 |
| Minimum turning circle | 10.84 m (35.56 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 7 |
| Gearbox type | Automatic transmission G-TRONIC PLUS |
| Front suspension | Independent type McPherson, Transverse stabilizer |
| Rear suspension | Independent multi-link suspension, Transverse stabilizer |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic |
| Tires size | 225/45 R17 |
| Wheel rims size | 7.5J x 17 |
Powertrain & Engine Architecture
The heart of the C 350 BlueEFFICIENCY was the M276.957 3.5-liter V6 engine. This engine was a significant departure from the older inline-six designs previously used by Mercedes-Benz. The M276 featured a 60-degree V-angle, contributing to a more compact engine bay footprint. It employed multi-point direct fuel injection, enhancing both power and fuel efficiency. The engine also incorporated variable valve timing (VVT) on both intake and exhaust camshafts, optimizing performance across the rev range. The 7G-TRONIC PLUS automatic transmission, a seven-speed unit, was known for its smooth and responsive shifts. It featured a torque converter lock-up clutch that engaged in most gears, improving fuel economy. The transmission also offered a manual shift mode for more driver control.
Driving Characteristics
The C 350 BlueEFFICIENCY offered a balanced driving experience. While not as overtly sporty as some of its rivals, it provided ample power for everyday driving and confident highway cruising. The 306 horsepower and 273 lb-ft of torque allowed for a 0-60 mph time of around 5.7 seconds. The 7G-TRONIC PLUS transmission contributed to smooth acceleration, although some drivers found it could be slightly hesitant in certain situations. Compared to the C 250, the C 350 offered a noticeable performance upgrade. However, it lacked the aggressive character of the C 63 AMG. The gear ratios were tuned for a blend of acceleration and fuel efficiency, prioritizing comfortable cruising over outright performance.
Equipment & Trim Levels
The C 350 BlueEFFICIENCY typically came well-equipped as standard. Features included leather upholstery, automatic climate control, a multi-function steering wheel, and a premium audio system. Optional extras included a navigation system, a panoramic sunroof, and advanced driver-assistance systems like lane keeping assist and blind spot monitoring. Interior trim options varied, with choices in wood veneers and aluminum accents. The standard dashboard configuration featured analog gauges with a central display screen for infotainment and vehicle information.
Chassis & Braking
The W204 C-Class utilized a four-wheel independent suspension system. The front suspension employed a McPherson strut design, while the rear featured a multi-link setup. This configuration provided a good balance of ride comfort and handling. The C 350 BlueEFFICIENCY 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. Stabilizer bars were fitted to both the front and rear axles to reduce body roll during cornering.
Market Reception & Comparison
The C 350 BlueEFFICIENCY was generally well-received by automotive critics. It was praised for its refined engine, comfortable ride, and well-appointed interior. However, some reviewers noted that the styling was somewhat conservative compared to its rivals. In terms of fuel economy, the C 350 offered competitive figures for its class, achieving around 34.6 mpg combined. Compared to the C 250, the C 350 offered a significant performance boost, but at the cost of slightly lower fuel economy. The C 63 AMG, while offering significantly more power, was considerably more expensive and less fuel-efficient.
Legacy
The M276 engine family, including the 3.5-liter variant found in the C 350 BlueEFFICIENCY, has proven to be relatively reliable. While some owners have reported issues with oil leaks and timing chain wear, these are not widespread problems. The 7G-TRONIC PLUS transmission is also generally considered to be durable, although regular fluid changes are essential for long-term reliability. Today, the W204 C 350 BlueEFFICIENCY remains a popular choice in the used car market, offering a good balance of luxury, performance, and value. Its relatively simple engine design and readily available parts contribute to its continued appeal.
