The Mercedes-Benz S 350, part of the W221 facelift generation produced from 2009 to 2011, represented a compelling blend of luxury, performance, and efficiency within the flagship S-Class range. Positioned as the entry point to the W221 lineup after the facelift, it offered a more accessible price point compared to the higher-powered S 550 and performance-oriented S 63 AMG models. This variant aimed to attract buyers who prioritized a refined driving experience and the prestige of the S-Class badge without the substantial cost associated with the top-tier trims. The S 350 utilized a naturally aspirated 3.5-liter V6 engine paired with Mercedes’ 7G-TRONIC automatic transmission, offering a balance between power and fuel economy.
Powertrain & Engine Architecture
The heart of the S 350 is the M 272.965 3.5-liter (3498 cm3 or 213.46 cu. in.) naturally aspirated V6 engine. This engine is a 60-degree V-engine, featuring a cast aluminum block and cylinder heads. It produces 272 horsepower (hp) at 6000 rpm and 350 Newton-meters (258.15 lb-ft) of torque between 2400 and 5000 rpm. The engine boasts a compression ratio of 10.7:1 and utilizes multi-port fuel injection. The valvetrain employs three valves per cylinder – two intake and one exhaust – contributing to improved breathing and efficiency.
The 7G-TRONIC automatic transmission (722.906) is a seven-speed planetary automatic transmission known for its smooth shifting and efficiency. It features a torque converter lock-up clutch that engages in most gears, reducing slippage and improving fuel economy. The transmission offers selectable driving modes, including Comfort and Sport, altering shift points to suit the driver’s preferences. The transmission is longitudinally mounted, driving the rear wheels.
Engine Code Specifics
The M 272 engine family, including the M 272.965, was known for its robust construction and relatively straightforward maintenance. However, early versions of the M 272 engine (prior to 2007) were susceptible to balance shaft sprocket wear, which could lead to engine noise. The 2009-2011 S 350 benefitted from revisions addressing this issue, making it a more reliable unit. Regular oil changes with the correct specification (Mercedes-Benz approved) are crucial for longevity. The engine’s timing chain is a potential maintenance item at higher mileages, requiring inspection and possible replacement.
Driving Characteristics
The S 350, with its 272 hp and 7-speed automatic, delivers a refined and comfortable driving experience. Acceleration from 0 to 100 km/h (0-62 mph) takes approximately 7.3 seconds, and 0-60 mph is achieved in around 6.9 seconds. While not as overtly powerful as the S 550 or S 63 AMG, the S 350 provides ample power for effortless cruising and confident overtaking. The 7G-TRONIC transmission contributes to smooth gear changes, minimizing disruptions to the driving experience.
Compared to the higher-output models, the S 350 feels less urgent in its acceleration. The gear ratios are tuned for comfort and fuel efficiency rather than outright performance. The automatic transmission, while responsive, doesn’t offer the same level of driver control as the optional manual gear selection found in some other S-Class variants. However, the S 350’s lighter weight compared to its more powerful siblings contributes to a more agile feel in corners.
Equipment & Trim Levels
The S 350 came standard with a comprehensive array of luxury features befitting its flagship status. Standard equipment typically included leather upholstery, power-adjustable heated front seats with memory function, dual-zone automatic climate control, a premium audio system, and a multi-function steering wheel. The interior featured wood trim accents and a high level of fit and finish.
Optional extras were plentiful, allowing buyers to personalize their S 350. Popular options included a panoramic sunroof, rear seat entertainment system, massaging seats, a parking assistance package, and advanced driver-assistance systems such as Distronic Plus adaptive cruise control and lane-keeping assist. Upholstery choices beyond the standard leather were available, as were various wood and trim options. The S 350 was often seen with the Sport Package, which included unique wheels, sport seats, and a sport-tuned suspension.
Chassis & Braking
The W221 S-Class chassis features a fully independent suspension system. The front suspension utilizes a five-link design, while the rear employs a multi-link setup. The S 350 typically featured steel springs with adaptive damping, providing a comfortable ride while maintaining good handling characteristics. Air suspension was available as an option, further enhancing ride quality and offering adjustable ride height.
Braking duties are handled by disc brakes on all four wheels, equipped with ABS (Anti-lock Braking System), Electronic Brakeforce Distribution (EBD), and Brake Assist. The braking system provides ample stopping power and a confident feel. The S 350’s curb weight of 1820 kg (4012.41 lbs) is relatively light for a full-size luxury sedan, contributing to its balanced handling.
Market Reception & Comparison
The S 350 was generally well-received by automotive critics as a sensible and refined option within the S-Class range. It was praised for its comfortable ride, luxurious interior, and relatively good fuel economy compared to the more powerful models. Fuel consumption figures averaged around 10-10.2 l/100 km (23.5-23.1 US mpg) combined. However, some critics noted that the engine lacked the outright performance of the S 550 and S 63 AMG.
Compared to the S 550, the S 350 offered a significant price advantage, making it more accessible to a wider range of buyers. The S 550, with its 5.5-liter V8 engine, delivered considerably more power and acceleration but at the cost of increased fuel consumption and a higher purchase price. The S 350 also offered better fuel economy than the S 63 AMG, which featured a high-performance 6.3-liter V8 engine.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | S-Class |
| Generation | S-Class (W221, facelift 2009) |
| Type | S 350 (272 Hp) G-TRONIC |
| Start of production | 2009 |
| End of production | 2011 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 14.6-14.8 l/100 km (16.1 – 15.9 US mpg) |
| Fuel consumption (extra urban) | 7.4-7.7 l/100 km (31.8 – 30.5 US mpg) |
| Fuel consumption (combined) | 10-10.2 l/100 km (23.5 – 23.1 US mpg) |
| CO2 emissions | 234-237 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.3 sec |
| Acceleration 0 – 62 mph | 7.3 sec |
| Acceleration 0 – 60 mph | 6.9 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Weight-to-power ratio | 6.7 kg/Hp |
| Weight-to-torque ratio | 5.2 kg/Nm |
| Power | 272 Hp @ 6000 rpm |
| Torque | 350 Nm @ 2400-5000 rpm (258.15 lb.-ft. @ 2400-5000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 272.965 |
| Engine displacement | 3498 cm3 (213.46 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Compression ratio | 10.7:1 |
| Fuel injection system | Multi-port manifold injection |
| Engine oil capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Coolant capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Kerb Weight | 1820 kg (4012.41 lbs) |
| Max. weight | 2490 kg (5489.51 lbs) |
| Max load | 670 kg (1477.1 lbs) |
| Trunk (boot) space | 560 l (19.78 cu. ft.) |
| Fuel tank capacity | 90 l (23.78 US gal | 19.8 UK gal) |
| Length | 5096 mm (200.63 in) |
| Width | 1871 mm (73.66 in) |
| Height | 1479 mm (58.23 in) |
| Wheelbase | 3035 mm (119.49 in) |
| Gears/Gearbox | 7 gears, automatic transmission G-TRONIC |
Legacy
The S 350 (W221 facelift) has proven to be a relatively reliable luxury sedan, particularly when well-maintained. The M 272 engine, while requiring periodic maintenance, is generally considered durable. The 7G-TRONIC transmission is also known for its longevity. On the used car market, the S 350 represents a more affordable entry point into S-Class ownership, offering a significant amount of luxury and technology for the price. However, potential buyers should be aware of the potential maintenance costs associated with a high-mileage luxury vehicle and ensure a thorough pre-purchase inspection is conducted.
