2002-2005 Mercedes-Benz S-class Long (V220 facelift ) S 400 CDI V8 (250 Hp) 5G-TRONIC

The Mercedes-Benz S 400 CDI Long, produced from 2002 to 2005, represented a compelling blend of luxury, performance, and diesel efficiency within the W220 S-Class range. This long-wheelbase variant, introduced with the 2002 facelift, catered to buyers prioritizing rear passenger space and a refined driving experience. Positioned as a mid-to-upper tier offering, the S 400 CDI slotted between the naturally aspirated V8 models and the high-performance AMG variants. It was primarily aimed at the European market, where diesel engines held significant popularity due to favorable taxation and fuel economy.

Technical Specifications

INTRODUCTION

The S 400 CDI Long, part of the facelifted W220 series (introduced in 2002), built upon the already impressive foundation of the W220 S-Class. The facelift brought subtle styling revisions, improved interior materials, and crucially, updated engine options. The “Long” designation indicated an extended wheelbase, adding approximately 120mm (4.7 inches) to the overall length, almost all of which benefited rear passenger legroom. This model was designed to appeal to executives and those who frequently traveled with passengers, offering a supremely comfortable and quiet ride. The 400 CDI variant specifically targeted markets where diesel power was favored, providing a compelling alternative to the gasoline-powered S 350 and S 500 models.

Powertrain & Engine Architecture

At the heart of the S 400 CDI Long lay the OM 628 DE 40 LA engine, a 4.0-liter V8 diesel. This engine was a significant advancement in diesel technology for Mercedes-Benz, featuring common rail direct injection and twin turbochargers with an intercooler. The twin-turbo setup minimized turbo lag and provided a broad, flat torque curve. The OM 628 engine boasted a high compression ratio of 18.5:1, contributing to its efficiency. The 5G-TRONIC automatic transmission, a five-speed unit, was specifically calibrated to handle the engine’s substantial torque output. This transmission offered smooth shifts and a driver-selectable Sport mode for more aggressive acceleration. The engine produced 250 horsepower at 4000 rpm and a robust 560 Nm (413 lb-ft) of torque between 1700 and 2600 rpm.

Driving Characteristics

The S 400 CDI Long delivered a driving experience characterized by effortless cruising and strong acceleration. While not as overtly sporty as the V12-powered S 600, the 400 CDI offered ample power for overtaking and maintaining high speeds on the Autobahn. The 5G-TRONIC transmission was well-matched to the engine, providing smooth and timely gear changes. The long wheelbase contributed to a remarkably stable and comfortable ride, effectively isolating passengers from road imperfections. The gear ratios were optimized for relaxed highway cruising, with a focus on maximizing fuel efficiency. Compared to the naturally aspirated S 350, the 400 CDI offered significantly more torque, resulting in quicker acceleration and a more confident feel when fully loaded. Compared to the S500, the CDI offered similar acceleration but with a noticeable advantage in fuel economy.

Equipment & Trim Levels

The S 400 CDI Long came standard with a comprehensive array of luxury features. These included leather upholstery, wood trim, automatic climate control, power-adjustable front seats with memory function, a premium sound system, and a multi-function steering wheel. Standard safety equipment included ABS, traction control, and a suite of airbags. Optional extras were plentiful, including a rear entertainment system, massaging seats, a panoramic sunroof, and advanced parking assist systems. The interior design was typical of Mercedes-Benz at the time, emphasizing understated elegance and high-quality materials. The long wheelbase allowed for more generous rear seat space, often equipped with individual climate controls and reclining seats.

Chassis & Braking

The S 400 CDI Long utilized a fully independent suspension system, featuring double wishbones at the front and a multi-link setup at the rear. This configuration provided a comfortable ride and precise handling. The braking system consisted of ventilated discs at the front and solid discs at the rear, coupled with ABS (Anti-lock Braking System). The hydraulic power steering offered a smooth and responsive feel. Stabilizer bars were fitted front and rear to minimize body roll during cornering. The suspension was tuned to prioritize comfort over outright sportiness, reflecting the car’s intended role as a luxury cruiser.

Market Reception & Comparison

The S 400 CDI Long was generally well-received by automotive critics. It was praised for its refined ride, powerful engine, and luxurious interior. The diesel engine’s fuel economy was a significant selling point, particularly in Europe. However, some critics noted that the diesel engine was not as quiet or refined as the gasoline-powered alternatives. Compared to the S 350, the 400 CDI offered superior performance and torque, but at a higher price point. Against the S 500, the CDI provided comparable performance with significantly better fuel economy. Reliability was generally good, although the complex common rail diesel injection system required careful maintenance.

Legacy

The Mercedes-Benz S 400 CDI Long remains a sought-after vehicle in the used car market, particularly among enthusiasts who appreciate its blend of luxury, performance, and efficiency. The OM 628 engine, while complex, is known for its durability when properly maintained. However, potential buyers should be aware of the potential for costly repairs related to the fuel injection system and turbochargers. The W220 S-Class, in general, is considered a landmark vehicle in Mercedes-Benz history, setting a new standard for luxury and technology. The S 400 CDI Long represents a particularly appealing variant for those seeking a comfortable, capable, and relatively economical grand tourer.