The Mercedes-Benz SL (R230) facelift, produced from 2006 to 2008, represented a significant evolution of the iconic roadster. Among the various engine options available, the SL 350 V6, powered by the M272.966 engine and paired with the 7G-TRONIC automatic transmission, occupied a crucial mid-range position in the lineup. This variant aimed to deliver a balance of performance, luxury, and relative affordability within the R230 generation, which itself was built on the Mercedes-Benz W230 platform.
The SL 350 V6: Positioning and Overview
The SL 350 V6 was introduced as a more accessible entry point into the R230 facelift range, slotting below the more powerful SL 55 AMG and SL 63 AMG models, as well as the supercharged SL 550. It offered a compelling alternative to the V8-powered options for buyers who prioritized a smoother, more fuel-efficient driving experience without sacrificing the prestige and open-air enjoyment associated with the SL nameplate. The facelift brought with it revised styling, updated technology, and refinements to the engine and transmission, enhancing the overall driving experience compared to the pre-2006 R230 models.
Powertrain & Engine Architecture
At the heart of the SL 350 V6 lies the M272.966 engine, a 3.5-liter naturally aspirated V6. This engine boasts a 60-degree V-angle and utilizes a three-valve-per-cylinder (two intake, one exhaust) DOHC valvetrain. The engine’s architecture is notable for its all-aluminum construction, contributing to a relatively lightweight design. Fuel delivery is managed by a multi-port fuel injection system, ensuring precise fuel atomization for optimal combustion. The engine produces 272 horsepower at 6000 rpm and 350 Nm (258.15 lb-ft) of torque between 2400 and 5000 rpm.
The engine is mated to Mercedes-Benz’s 7G-TRONIC seven-speed automatic transmission. This transmission, a significant advancement over previous iterations, offers smooth and responsive gear changes. It features a torque converter lock-up clutch that engages in most gears, improving fuel efficiency. The 7G-TRONIC also incorporates a manual shift mode, allowing drivers to exert more control over gear selection. The transmission’s gear ratios are optimized for both acceleration and cruising, providing a balance between performance and comfort.
Driving Characteristics
The SL 350 V6 delivers a refined and comfortable driving experience. While not as overtly powerful as its V8 counterparts, the 3.5-liter engine provides ample power for both city driving and highway cruising. Acceleration from 0 to 60 mph is achieved in approximately 6.3 seconds, and the car is electronically limited to a top speed of 155.34 mph (250 km/h). The 7G-TRONIC transmission contributes to a seamless power delivery, minimizing shift shock and maximizing efficiency.
Compared to the SL 55 and SL 63 AMG models, the SL 350 V6 offers a more relaxed and less aggressive driving experience. The V8 engines in those models provide significantly more horsepower and torque, resulting in quicker acceleration and a more visceral sound. However, the SL 350 V6’s lighter weight and more balanced chassis contribute to nimble handling and a comfortable ride. The automatic transmission, while lacking the immediacy of a manual gearbox, provides convenience and ease of use, particularly in urban environments.
Equipment & Trim Levels
The SL 350 V6 came standard with a comprehensive array of luxury features. These included leather upholstery, automatic climate control, power-adjustable seats with memory function, a premium sound system, and a retractable hardtop. Standard safety features included ABS, traction control, and multiple airbags. Optional extras included features such as the COMAND infotainment system with navigation, bi-xenon headlights, parking sensors, and upgraded interior trim options. The interior design featured a blend of classic Mercedes-Benz elegance and modern technology, with a focus on comfort and convenience.
Chassis & Braking
The SL 350 V6 utilizes a sophisticated chassis design featuring an independent multi-link suspension at both the front and rear. This suspension setup provides a comfortable ride while maintaining excellent handling characteristics. Coil springs and shock absorbers are tuned to balance ride comfort and body control. The car is equipped with ventilated disc brakes on all four wheels, providing ample stopping power. The anti-lock braking system (ABS) prevents wheel lockup during hard braking, enhancing stability and control. The steering system is a hydraulic power-assisted rack and pinion setup, offering precise and responsive steering feel.
Market Reception & Comparison
The SL 350 V6 was generally well-received by automotive critics. It was praised for its refined engine, smooth transmission, comfortable ride, and luxurious interior. However, some critics noted that the engine lacked the outright power of the V8 models. Fuel economy was considered a strong point, with combined fuel consumption figures of around 22.8 US mpg (10.3 l/100 km). In terms of reliability, the M272 engine is generally considered to be a robust and dependable unit, although regular maintenance is essential. Compared to other roadsters in its class, such as the BMW Z4 and Porsche Boxster, the SL 350 V6 offered a more luxurious and comfortable experience, albeit at a higher price point.
Technical Specifications
| Engine Model/Code | M 272.966 |
| 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 | 10.7:1 |
| Number of Valves per Cylinder | 4 |
| Fuel Injection System | Multi-port manifold injection |
| Engine Aspiration | Naturally aspirated |
| Valvetrain | DOHC |
| Power | 272 Hp @ 6000 rpm |
| Torque | 350 Nm @ 2400-5000 rpm (258.15 lb.-ft. @ 2400-5000 rpm) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0-100 km/h | 6.6 sec |
| Acceleration 0-60 mph | 6.3 sec |
| Maximum Speed | 250 km/h (155.34 mph) – Electronically limited |
| Kerb Weight | 1750 kg (3858.09 lbs.) |
| Fuel Tank Capacity | 80 l (21.13 US gal | 17.6 UK gal) |
| Transmission | 7-speed automatic (7G-TRONIC) |
Legacy
The SL 350 V6, while not the most sought-after variant of the R230 facelift, remains a desirable option in the used car market. Its combination of luxury, performance, and relative affordability makes it an attractive choice for buyers seeking a stylish and comfortable roadster. The M272 engine has proven to be a reliable powerplant when properly maintained, and the 7G-TRONIC transmission is known for its smoothness and durability. As with any used vehicle, potential buyers should carefully inspect the car’s maintenance history and overall condition before making a purchase. The SL 350 V6 represents a sweet spot in the R230 lineup, offering a compelling blend of Mercedes-Benz engineering and open-air driving enjoyment.
