The Mercedes-Benz S 350 BlueEFFICIENCY 4MATIC, introduced as part of the facelifted V221 S-Class Long wheelbase in 2009, represented a sophisticated balance of luxury, performance, and efficiency within the Mercedes-Benz flagship range. Production spanned from 2011 to 2013, positioning this variant as a middle-ground offering in the S-Class lineup. It provided a refined experience without the outright power of the S 550 or the fuel economy focus of the S 350 CDI. The S 350 4MATIC primarily targeted buyers desiring a comfortable, technologically advanced sedan with the added security of all-wheel drive, appealing to both executive transportation and private luxury car enthusiasts. The “Long” designation signifies an extended wheelbase, prioritizing rear passenger comfort – a crucial feature in markets where chauffeur-driven travel is prevalent.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | S-class |
| Generation | S-class Long (V221, facelift 2009) |
| Type (Engine) | S 350 BlueEFFICIENCY (306 Hp) 4MATIC G-TRONIC |
| Start of production | 2011 year |
| End of production | 2013 year |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – urban | 10.8-10.9 l/100 km (21.8 – 21.6 US mpg, 26.2 – 25.9 UK mpg, 9.3 – 9.2 km/l) |
| Fuel consumption (economy) – extra urban | 6.5-6.7 l/100 km (36.2 – 35.1 US mpg, 43.5 – 42.2 UK mpg, 15.4 – 14.9 km/l) |
| Fuel consumption (economy) – combined | 8.1-8.3 l/100 km (29 – 28.3 US mpg, 34.9 – 34 UK mpg, 12.3 – 12 km/l) |
| CO2 emissions | 189-193 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 6.9 sec |
| Acceleration 0 – 62 mph | 6.9 sec |
| Acceleration 0 – 60 mph | 6.6 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 6.4 kg/Hp, 155.3 Hp/tonne |
| Weight-to-torque ratio | 5.3 kg/Nm, 187.8 Nm/tonne |
| Power | 306 Hp @ 6500 rpm |
| Power per litre | 87.5 Hp/l |
| Torque | 370 Nm @ 3500 rpm (272.9 lb.-ft. @ 3500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 276.950 |
| Engine displacement | 3498 cm3 (213.46 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Compression ratio | 12:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Kerb Weight | 1970 kg (4343.11 lbs.) |
| Max. weight | 2630 kg (5798.16 lbs.) |
| Max load | 660 kg (1455.05 lbs.) |
| Trunk (boot) space – minimum | 560 l (19.78 cu. ft.) |
| Fuel tank capacity | 83 l (21.93 US gal | 18.26 UK gal) |
| Length | 5226 mm (205.75 in.) |
| Width | 1871 mm (73.66 in.) |
| Width including mirrors | 2120 mm (83.46 in.) |
| Height | 1479 mm (58.23 in.) |
| Wheelbase | 3165 mm (124.61 in.) |
| Front track | 1600 mm (62.99 in.) |
| Rear (Back) track | 1606 mm (63.23 in.) |
| Front overhang | 888 mm (34.96 in.) |
| Rear overhang | 1173 mm (46.18 in.) |
| Minimum turning circle | 12.2 m (40.03 ft.) |
| Drive wheel | All wheel drive (4×4) |
| Number of gears and type of gearbox | 7 gears, automatic transmission G-TRONIC |
| Front brakes | Disc |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Tires size | 235/55 R17 |
| Wheel rims size | 17 |
Powertrain & Engine Architecture
The S 350 BlueEFFICIENCY 4MATIC was powered by the M276.950 3.5-liter naturally aspirated V6 engine. This engine was a key component of Mercedes-Benz’s modular engine family, celebrated for its smooth operation and relatively high efficiency. It featured a 60-degree V-angle, an aluminum alloy block and cylinder heads, and a sophisticated direct injection system. The direct injection system, capable of operating at pressures up to 200 bar, enabled precise fuel metering and enhanced combustion efficiency. Variable valve timing (VVT) on both intake and exhaust camshafts further optimized performance across the engine’s operating range. The “BlueEFFICIENCY” designation signified the inclusion of fuel-saving technologies, including optimized aerodynamics, lightweight construction, and a demand-controlled auxiliary cooling system. The engine was coupled with the 7G-TRONIC seven-speed automatic transmission, known for its smooth and responsive gear changes. This transmission incorporated a torque converter lockup clutch to minimize slippage and improve fuel economy. The 4MATIC all-wheel-drive system distributed power between the front and rear axles, improving traction and stability, especially in challenging weather conditions.
Driving Characteristics
The S 350 4MATIC delivered a refined and comfortable driving experience. While not focused on outright sportiness, the 306 horsepower and 370 lb-ft of torque provided sufficient power for effortless cruising and confident overtaking maneuvers. Acceleration from 0-60 mph occurred in approximately 6.6 seconds, a respectable figure for a large luxury sedan. The 7G-TRONIC transmission contributed to seamless gear changes, and the all-wheel-drive system inspired confidence in all conditions. Compared to the more powerful S 550, the S 350 offered a less aggressive acceleration profile, but prioritized a more relaxed and fuel-efficient driving experience. The gear ratios were calibrated for comfort and efficiency, emphasizing smooth transitions over rapid downshifts. In contrast to the diesel-powered S 350 CDI, the gasoline S 350 provided a more linear power delivery and a quieter engine note, though at the cost of fuel economy.
Equipment & Trim Levels
The S 350 BlueEFFICIENCY 4MATIC came standard with a comprehensive suite of luxury features. Interior appointments typically included leather upholstery, wood trim, and a multi-function steering wheel. Standard equipment also encompassed automatic climate control, a premium audio system, power-adjustable front seats with memory function, and a sunroof. The extended wheelbase provided generous rear legroom, making it particularly appealing to rear-seat passengers. Optional extras included features such as a rear entertainment system, massaging seats, a panoramic sunroof, and advanced driver-assistance systems like Distronic Plus adaptive cruise control and lane-keeping assist. Trim levels were relatively limited, with most personalization achieved through the selection of individual options.
Chassis & Braking
The V221 S-Class featured an air suspension system (AIRMATIC) as standard, providing an exceptionally smooth and comfortable ride. The system automatically adjusted suspension damping and ride height based on road conditions and driving style. The S 350 4MATIC utilized disc brakes on all four wheels, equipped with ABS (Anti-lock Braking System), Electronic Stability Program (ESP), and Brake Assist. The suspension geometry was tuned to balance comfort and handling, delivering a stable and predictable driving experience. Stabilizer bars were fitted to both the front and rear axles to minimize body roll during cornering.
Market Reception & Comparison
The S 350 BlueEFFICIENCY 4MATIC received generally positive reviews from automotive critics. It was lauded for its comfortable ride, refined interior, and efficient engine. However, some reviewers noted that its performance wasn’t as exhilarating as that of the S 550. Compared to its siblings, the S 350 offered a compelling value proposition, providing a substantial amount of luxury and technology at a lower price point. Its fuel economy was competitive within the large luxury sedan segment, and its all-wheel-drive system offered added security and confidence.
Legacy
The M276 engine family, including the M276.950 in the S 350, proved to be relatively reliable, though preventative maintenance is essential. Common issues include oil leaks from the valve cover gaskets and potential problems with the timing chain tensioners on higher-mileage vehicles. The 7G-TRONIC transmission is generally robust, but regular fluid changes are crucial for maintaining smooth operation. Today, the V221 S-Class, including the S 350 4MATIC, represents a significant value in the used car market. It offers a level of luxury and technology that remains competitive with newer vehicles, and its relatively affordable price makes it an attractive option for buyers seeking a high-end sedan without the premium price tag.
