2011-2013 Mercedes-Benz S-class (W221 facelift ) S 350 BlueEFFICIENCY (306 Hp) 4MATIC G-TRONIC

The Mercedes-Benz S 350 BlueEFFICIENCY 4MATIC, produced from 2011 to 2013, was a key variant within the W221 facelift generation of the S-Class. Representing a balance between performance, efficiency, and luxury, it occupied a mid-range position in the S-Class lineup, slotting below the more powerful S 550 and S 63 AMG models, but above the base S 300 models available in some markets. This model aimed to provide a sophisticated driving experience with reduced fuel consumption compared to its higher-powered siblings, while still maintaining the flagship comfort and technology expected of the S-Class.

Powertrain & Engine Architecture

The S 350 BlueEFFICIENCY 4MATIC was powered by the M276.950 3.5-liter naturally aspirated V6 gasoline engine. This engine, a cornerstone of Mercedes-Benz’s engine lineup during this period, featured a 60-degree V-angle and all-aluminum construction. It produced 306 horsepower at 6500 rpm and 370 Nm (272.9 lb-ft) of torque at 3500 rpm, delivering a power-to-liter ratio of 87.5 hp/l. The engine employed direct fuel injection, a technology that improved both power output and fuel efficiency. The valvetrain utilized four valves per cylinder, contributing to optimized gas flow and engine responsiveness.

The “BlueEFFICIENCY” designation indicated the inclusion of various fuel-saving technologies, including optimized engine management, reduced-friction components, and aerodynamic enhancements. The engine was paired exclusively with the 7G-TRONIC seven-speed automatic transmission. This transmission, known for its smooth and responsive shifts, was a crucial component in maximizing fuel economy and providing a comfortable driving experience. The 7G-TRONIC featured a torque converter lock-up clutch that engaged at higher speeds to reduce slippage and improve efficiency. The transmission was electronically controlled, adapting shift points based on driving conditions and driver input.

Transmission Details

The 7G-TRONIC transmission in the S 350 BlueEFFICIENCY 4MATIC offered a wide range of gear ratios designed to balance acceleration and fuel economy. First gear was relatively short for quick off-the-line acceleration, while higher gears were geared for efficient cruising. The transmission also featured a manual shift mode, allowing drivers to select gears manually for greater control. The transmission’s programming was specifically tuned to complement the characteristics of the 3.5-liter V6 engine, providing seamless and refined gear changes.

Driving Characteristics

The S 350 BlueEFFICIENCY 4MATIC offered a refined and comfortable driving experience. While not as overtly powerful as the V8-powered S-Class models, the 3.5-liter V6 provided ample power for everyday driving and highway cruising. Acceleration from 0 to 60 mph was achieved in approximately 6.6 seconds, and the car had a governed top speed of 155.34 mph (250 km/h). The 7G-TRONIC transmission contributed to smooth and effortless acceleration, with minimal noticeable shift shock.

Compared to the more powerful S 550, the S 350 offered a more balanced driving experience, with less emphasis on outright performance and more focus on comfort and efficiency. The S 350 also differed from the diesel-powered S 350 CDI models, which offered higher torque figures but a different engine character. The naturally aspirated V6 in the S 350 BlueEFFICIENCY provided a linear power delivery, making it easy to modulate throttle response and maintain control in various driving situations.

Equipment & Trim Levels

The S 350 BlueEFFICIENCY 4MATIC came standard with a comprehensive array of luxury features, befitting its status as a flagship sedan. Standard equipment included leather upholstery, power-adjustable front seats with memory function, dual-zone automatic climate control, a premium audio system, and a navigation system. The interior featured high-quality materials and meticulous craftsmanship, creating a luxurious and inviting cabin environment. Wood trim was standard, with various options available to customize the interior appearance.

Optional extras included features such as a rear seat entertainment system, massaging seats, a panoramic sunroof, and advanced driver-assistance systems like Distronic Plus adaptive cruise control and lane-keeping assist. The 4MATIC all-wheel-drive system was standard, providing enhanced traction and stability in all weather conditions. Exterior options included various wheel designs and paint colors.

Chassis & Braking

The W221 S-Class chassis featured an independent suspension system at all four corners, providing a smooth and comfortable ride. The front suspension utilized a multi-link design with air springs and adaptive damping, while the rear suspension employed a similar setup. The air suspension system allowed the ride height to be adjusted, providing increased ground clearance for navigating rough roads or lowering the vehicle for improved aerodynamics at high speeds.

The braking system consisted of disc brakes at all four wheels, with ABS (Anti-lock Braking System) and Electronic Stability Program (ESP) as standard features. The braking system provided ample stopping power and excellent control in both dry and wet conditions. The S 350 BlueEFFICIENCY 4MATIC typically featured 17-inch alloy wheels with 235/55 R17 tires.

Market Reception & Comparison

The S 350 BlueEFFICIENCY 4MATIC was generally well-received by automotive critics. It was praised for its comfortable ride, refined interior, and fuel efficiency. While some critics noted that the 3.5-liter V6 engine lacked the outright performance of the V8 models, it was considered adequate for most drivers. Fuel economy figures were competitive for a luxury sedan of its size, with combined fuel consumption ranging from 8.1 to 8.3 l/100 km (29-28.3 US mpg).

Compared to the S 550, the S 350 offered a more affordable entry point into the S-Class range, while still providing a high level of luxury and technology. The S 350 CDI diesel model offered superior fuel economy and torque, but some buyers preferred the smoother and quieter operation of the gasoline engine. Reliability was generally good, although like all complex vehicles, the S-Class could be subject to occasional maintenance issues.

Technical Specifications

Legacy

The M276 engine family, including the 3.5-liter variant used in the S 350 BlueEFFICIENCY 4MATIC, proved to be a reliable and durable powertrain. While some early examples experienced minor issues with the balance shaft, these were generally addressed through warranty repairs. Today, well-maintained S 350 BlueEFFICIENCY 4MATIC models represent a compelling value in the used luxury car market. They offer a high level of comfort, technology, and refinement at a more affordable price point than newer S-Class models. The 7G-TRONIC transmission is also known for its longevity, provided it has been properly serviced. The combination of a smooth-running engine, a refined transmission, and a luxurious interior makes the S 350 BlueEFFICIENCY 4MATIC a desirable choice for buyers seeking a sophisticated and comfortable grand touring sedan.