2001-2006 Mercedes-Benz SL (R230) AMG SL 55 V8 (476 Hp) Automatic

The Mercedes-Benz SL (R230) AMG SL 55 V8 Automatic, produced from December 2001 to January 2006, represents a high-performance iteration of the R230 SL-Class roadster. Positioned as the flagship model within the R230 range during its production run, it offered a significant step up in power and luxury compared to the standard SL 350 and SL 500 variants. The R230 generation itself marked a return to the traditional roadster layout after the previous R129 generation, emphasizing both grand touring comfort and sporty handling. This particular variant, with its supercharged 5.4-liter V8 engine and five-speed automatic transmission, catered to buyers seeking exhilarating performance combined with the convenience of an automatic gearbox.

AMG SL 55 Powertrain & Engine Architecture

At the heart of the AMG SL 55 lies the M113.992 engine, a 5.4-liter (5439 cc / 331.91 cu. in.) naturally aspirated V8 engine enhanced with a Lysholm-type supercharger and intercooler. This configuration allowed for a substantial power output of 476 hp (355 kW) at 6100 rpm and 700 Nm (516.29 lb-ft) of torque available from 2650 to 4500 rpm. The engine utilizes multi-port fuel injection and a single overhead camshaft (SOHC) valvetrain with three valves per cylinder. The supercharger, unlike turbochargers, provides instant boost response, contributing to the engine’s characteristic linear power delivery.

The engine is mounted longitudinally in the front of the vehicle. The five-speed automatic transmission (specifically the 722.6) was a robust unit designed to handle the high torque output of the supercharged V8. While not as technologically advanced as some later automatic transmissions, it offered smooth shifts and a relatively quick response. The transmission featured a torque converter lock-up clutch to improve fuel efficiency at cruising speeds. The drivetrain is rear-wheel drive, contributing to the car’s sporty handling characteristics.

Engine Specifications

Key engine specifications include a compression ratio of 9:1, a cylinder bore of 97 mm (3.82 in), and a piston stroke of 92 mm (3.62 in). The engine requires 8.5 liters (8.98 US qt / 7.48 UK qt) of engine oil and 13 liters (13.74 US qt / 11.44 UK qt) of coolant. It meets Euro 4 emission standards.

Driving Characteristics

The AMG SL 55 delivers a distinctly powerful driving experience. The supercharged V8 provides strong acceleration across the entire rev range, with a 0-60 mph time of approximately 4.5 seconds and a 0-100 km/h time of 4.7 seconds. The electronically limited top speed is 250 km/h (155.34 mph). Compared to the naturally aspirated SL 500, the SL 55 offers significantly more power and torque, resulting in noticeably quicker acceleration and a more engaging driving experience. While the five-speed automatic transmission is capable, it doesn’t offer the same level of control or responsiveness as the seven-speed automatic found in later SL models or the manual transmissions available in other SL variants. The gear ratios are tuned for a balance between acceleration and cruising comfort. The car feels substantial and planted on the road, thanks to its weight and well-tuned suspension.

Equipment & Trim Levels

The AMG SL 55 came standard with a comprehensive list of features befitting its flagship status. Interior appointments included premium leather upholstery, wood trim, and power-adjustable seats with memory function. Standard equipment also included automatic climate control, a premium sound system, and a multi-function steering wheel. Optional extras included features such as Distronic adaptive cruise control, Keyless-Go, and upgraded interior trim packages. The exterior featured AMG-specific body styling, including unique front and rear bumpers, side skirts, and wheels. The standard wheel size was 8.5J x 18 inches in the front and 9.5J x 18 inches in the rear, fitted with 255/40 R18 and 285/35 R18 tires respectively.

Chassis & Braking

The R230 SL 55 utilizes an independent multi-link suspension system at both the front and rear, incorporating hydraulic elements. This suspension setup provides a comfortable ride while maintaining good handling characteristics. The car is equipped with ventilated disc brakes on all four wheels, coupled with an Anti-lock Braking System (ABS) for enhanced safety. The steering system is a hydraulic power-assisted rack and pinion setup, providing precise and responsive steering feel. The kerb weight of the vehicle is 1880 kg (4144.69 lbs), with a maximum weight of 2200 kg (4850.17 lbs) and a maximum load capacity of 320 kg (705.48 lbs).

Market Reception & Comparison

The AMG SL 55 was generally well-received by automotive critics, who praised its powerful engine, comfortable ride, and luxurious interior. However, some criticisms were leveled at the car’s weight and the relatively dated five-speed automatic transmission. Fuel economy was also a concern, with combined fuel consumption figures of 14.2 l/100 km (16.6 US mpg / 19.9 UK mpg) and CO2 emissions of 340 g/km. Compared to the SL 500, the SL 55 offered a significant performance advantage but at a higher price point and with slightly worse fuel economy. Compared to the later SL 63 AMG models (which featured a larger engine and a more advanced transmission), the SL 55 represented a more accessible entry point into the world of high-performance SL roadsters.

Technical Specifications

Legacy

The AMG SL 55 remains a desirable used car today, appreciated for its powerful engine and classic roadster styling. While not the most fuel-efficient or technologically advanced vehicle, it offers a compelling combination of performance, luxury, and exclusivity. The M113 engine is generally considered to be reliable, although regular maintenance is essential. Common issues include potential oil leaks and wear on the supercharger clutch. The five-speed automatic transmission is also generally reliable, but may exhibit some wear and tear over time. The R230 SL 55 represents a significant chapter in the SL’s history, bridging the gap between the classic roadsters of the past and the more modern, technologically advanced SL models of today.