2010-2013 Mercedes-Benz S-class (W221 facelift ) S 350 CDI BlueTEC (258 Hp) 4MATIC G-TRONIC

The Mercedes-Benz S 350 CDI BlueTEC 4MATIC, produced from 2010 to 2013, was a diesel-powered variant of the W221 S-Class following the 2009 facelift. Positioned as a mid-range offering within the S-Class lineup, it aimed to provide a balance between luxury, performance, and fuel efficiency. This model represented a significant step in Mercedes-Benz’s efforts to combine large displacement engines with advanced emissions control technology, specifically the BlueTEC system, to meet increasingly stringent environmental regulations. The W221 S-Class, built on the 1HX0/A3 platform, represented a leap forward in automotive technology, and the S 350 CDI 4MATIC was a key component of its success, particularly in European markets.

Powertrain & Engine Architecture

The heart of the S 350 CDI BlueTEC 4MATIC is the OM642.868 3.0-liter V6 diesel engine. This engine is a longitudinally mounted, turbocharged and intercooled common rail direct injection diesel. It produces 258 horsepower at 3600 rpm and a substantial 620 Nm (457.29 lb-ft) of torque between 1600 and 2400 rpm. The high torque output, characteristic of diesel engines, provides strong acceleration and effortless cruising. The engine features a compression ratio of 15.5:1 and 4 valves per cylinder.

The BlueTEC system is central to the engine’s operation. It incorporates a diesel particulate filter (DPF) to trap soot, and an SCR (Selective Catalytic Reduction) system that uses AdBlue (a urea solution) to reduce nitrogen oxide (NOx) emissions. This allowed the S 350 CDI to meet Euro 6 emission standards. The fuel injection system utilizes piezo injectors for precise fuel delivery and optimized combustion. The engine’s oil capacity is 8 liters (8.45 US qt / 7.04 UK qt) and requires a specific oil specification as outlined by Mercedes-Benz.

The engine is paired with the 7G-TRONIC automatic transmission, a seven-speed torque converter automatic. This transmission is known for its smooth shifting and efficiency. The gear ratios are tuned to maximize both fuel economy and performance, with a focus on utilizing the engine’s abundant low-end torque. The transmission features a manual shift mode, allowing the driver some control over gear selection, but the primary focus is on providing a relaxed and refined driving experience.

Engine Code Specifics

The OM642.868 engine code designates a specific iteration of the OM642 V6 diesel family. This particular version was optimized for the W221 S-Class, incorporating enhancements to reduce noise, vibration, and harshness (NVH) levels, befitting the luxury vehicle’s character. The engine management system was also calibrated to work seamlessly with the 7G-TRONIC transmission and the 4MATIC all-wheel-drive system.

Driving Characteristics

The S 350 CDI BlueTEC 4MATIC delivers a driving experience focused on comfort and effortless power. The 620 Nm of torque is available from relatively low engine speeds, providing strong acceleration in everyday driving situations. While not as overtly sporty as the S 500 or AMG variants, the S 350 CDI offers a 0-100 km/h (0-62 mph) time of 7.1 seconds, and a 0-60 mph time of approximately 6.7 seconds. The 7G-TRONIC transmission contributes to smooth and seamless gear changes, enhancing the overall refinement.

Compared to the gasoline-powered S-Class models, the S 350 CDI offers significantly better fuel economy. The 4MATIC all-wheel-drive system provides enhanced traction and stability, particularly in adverse weather conditions. However, the added weight of the all-wheel-drive system and the diesel engine does result in a slightly higher curb weight compared to rear-wheel-drive S-Class models. The steering is precise and well-weighted, providing a confident feel on the road.

Equipment & Trim Levels

The S 350 CDI BlueTEC 4MATIC came standard with a comprehensive array of luxury features. These included leather upholstery, power-adjustable heated and ventilated front seats, a premium sound system, dual-zone automatic climate control, and a navigation system. Standard safety features included ABS, ESP, multiple airbags, and a tire pressure monitoring system.

Optional extras were plentiful, allowing buyers to customize their S-Class to their preferences. These included a panoramic sunroof, rear seat entertainment system, massaging seats, a driver assistance package (including adaptive cruise control and lane keeping assist), and various interior trim options. The dashboard configuration was typical of the W221 S-Class, featuring a high-quality materials and a user-friendly interface. The interior ambiance was designed to create a luxurious and relaxing environment for both the driver and passengers.

Chassis & Braking

The S 350 CDI BlueTEC 4MATIC utilizes a fully independent suspension system, with multi-link suspension at both the front and rear. This provides a comfortable ride and excellent handling characteristics. The suspension is electronically controlled, allowing the driver to adjust the damping settings to suit their preferences. The 4MATIC all-wheel-drive system distributes power to all four wheels, enhancing traction and stability.

The braking system consists of disc brakes on all four wheels. ABS (Anti-lock Braking System) and ESP (Electronic Stability Program) are standard features, providing enhanced braking performance and stability. The vehicle is equipped with 235/55 R17 tires mounted on 17-inch alloy wheels. The steering system is a rack and pinion type, providing precise and responsive steering feel.

Market Reception & Comparison

The S 350 CDI BlueTEC 4MATIC was generally well-received by automotive critics. It was praised for its fuel efficiency, comfortable ride, and luxurious interior. The diesel engine’s strong torque output was also appreciated, providing effortless performance. However, some critics noted that the diesel engine was not as refined as the gasoline-powered engines in the S-Class lineup.

Compared to the S 500, the S 350 CDI offered significantly better fuel economy, but less outright performance. The S 350 CDI was also more affordable than the S 500, making it a more accessible option for buyers who wanted the luxury and prestige of the S-Class without the higher price tag. In terms of reliability, the OM642 engine is generally considered to be a robust and durable unit, but the BlueTEC system can be complex and potentially expensive to repair if issues arise.

Technical Specifications

Legacy

The Mercedes-Benz S 350 CDI BlueTEC 4MATIC represents a significant chapter in the evolution of diesel technology within the luxury car segment. The OM642 engine, while superseded by newer designs, remains a respected powerplant known for its durability and fuel efficiency. On the used car market, these vehicles offer a compelling combination of luxury, performance, and value. However, potential buyers should be aware of the potential maintenance costs associated with the BlueTEC system, particularly the DPF and SCR components. Properly maintained, the S 350 CDI BlueTEC 4MATIC can provide many years of reliable and comfortable motoring, continuing the S-Class tradition of automotive excellence.