The Mercedes-Benz S 400 CDI Long, produced between 1999 and 2002 as part of the V220 generation of the S-Class, represented a significant offering in the luxury sedan segment. This extended-wheelbase variant, often referred to as the “Long” version, catered to buyers prioritizing rear passenger comfort. The S 400 CDI distinguished itself with a powerful diesel V8 engine paired with a five-speed automatic transmission, aiming to deliver both performance and fuel efficiency within the flagship S-Class range. It was positioned as a premium offering, bridging the gap between the standard S-Class models and the higher-performance S 500 and S 600 variants.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | S-class |
| Generation | S-class Long (V220) |
| Type (Engine) | S 400 CDI V8 (250 Hp) 5G-TRONIC |
| Start of production | 1999 |
| End of production | 2002 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 14.2 l/100 km (16.6 US mpg, 19.9 UK mpg, 7 km/l) |
| Fuel consumption (extra urban) | 7 l/100 km (33.6 US mpg, 40.4 UK mpg, 14.3 km/l) |
| Fuel consumption (combined) | 9.6 l/100 km (24.5 US mpg, 29.4 UK mpg, 10.4 km/l) |
| CO2 emissions | 253 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 7.8 sec |
| Acceleration 0 – 62 mph | 7.8 sec |
| Acceleration 0 – 60 mph | 7.4 sec |
| Maximum speed | 250 km/h (155.34 mph) |
| Weight-to-power ratio | 7.7 kg/Hp, 130.2 Hp/tonne |
| Weight-to-torque ratio | 3.4 kg/Nm, 291.7 Nm/tonne |
| Power | 250 Hp @ 4000 rpm |
| Power per litre | 62.6 Hp/l |
| Torque | 560 Nm @ 1700-2600 rpm (413.03 lb.-ft. @ 1700-2600 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 628 DE 40 LA/628.960 |
| Engine displacement | 3996 cm3 (243.85 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 86 mm (3.39 in.) |
| Piston Stroke | 86 mm (3.39 in.) |
| Compression ratio | 18.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | BiTurbo, Intercooler |
| Engine oil capacity | 10 l (10.57 US qt | 8.8 UK qt) |
| Coolant | 16.5 l (17.44 US qt | 14.52 UK qt) |
| Kerb Weight | 1920 kg (4232.88 lbs.) |
| Max. weight | 2460 kg (5423.37 lbs.) |
| Max load | 540 kg (1190.5 lbs.) |
| Trunk (boot) space – minimum | 500 l (17.66 cu. ft.) |
| Fuel tank capacity | 88 l (23.25 US gal | 19.36 UK gal) |
| Length | 5158 mm (203.07 in.) |
| Width | 1855 mm (73.03 in.) |
| Width including mirrors | 2092 mm (82.36 in.) |
| Height | 1444 mm (56.85 in.) |
| Wheelbase | 3085 mm (121.46 in.) |
| Front track | 1574 mm (61.97 in.) |
| Rear (Back) track | 1574 mm (61.97 in.) |
| Front overhang | 867 mm (34.13 in.) |
| Rear overhang | 1206 mm (47.48 in.) |
| Minimum turning circle | 11.7 m (38.39 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Drive wheel | Rear wheel drive |
| Number of gears | 5 |
| Gearbox type | automatic transmission G-TRONIC |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | 225/60 R16W |
| Wheel rims size | 7.5J x 16 |
Powertrain & Engine Architecture
The heart of the S 400 CDI Long was the OM 628 DE 40 LA V8 diesel engine, a 4.0-liter unit producing 250 horsepower at 4000 rpm and a substantial 560 Nm (413 lb-ft) of torque between 1700 and 2600 rpm. This engine utilized a sophisticated common rail direct injection system, enabling precise fuel delivery and contributing to both power output and improved emissions. The engine was equipped with twin turbochargers and an intercooler, enhancing responsiveness and minimizing turbo lag. The five-speed 5G-TRONIC automatic transmission was specifically tuned to handle the engine’s torque characteristics, providing smooth and refined gear changes. This transmission featured adaptive shift programming, adjusting to the driver’s style and road conditions.
Driving Characteristics
The S 400 CDI Long offered a compelling blend of performance and comfort. While not as overtly sporty as the gasoline-powered S 500, the diesel V8 provided ample power for effortless cruising and confident overtaking. The 5G-TRONIC transmission contributed to a relaxed driving experience, with well-spaced gear ratios optimized for both fuel economy and acceleration. The long wheelbase enhanced ride quality, absorbing bumps and providing a smooth, stable ride. Compared to the standard S-Class, the CDI offered a different character – prioritizing torque and fuel efficiency over outright horsepower. The manual transmission options available on other S-Class models were not offered with the 400 CDI, focusing solely on the automatic for a more luxurious experience.
Equipment & Trim Levels
The S 400 CDI Long typically came well-equipped, reflecting its position as a premium model. Standard features included leather upholstery, wood trim, automatic climate control, power-adjustable front seats with memory function, and a high-end audio system. The extended wheelbase translated into increased rear legroom, making it particularly appealing to passengers. Optional extras included a rear entertainment system, massaging seats, a premium sound system upgrade, and various driver-assistance features. The interior design was characterized by Mercedes-Benz’s signature understated elegance, with a focus on quality materials and craftsmanship.
Chassis & Braking
The S 400 CDI Long utilized a robust chassis with independent suspension on all four wheels. The front suspension featured multi-link design, while the rear employed a semi-trailing arm setup. This configuration provided a comfortable ride and good handling characteristics. The braking system consisted of ventilated disc brakes at the front and solid disc brakes at the rear, coupled with ABS (Anti-lock Braking System) for enhanced safety. The steering was a hydraulic power-assisted rack and pinion system, offering precise and responsive control.
Market Reception & Comparison
The S 400 CDI Long was generally well-received by automotive critics, who praised its powerful engine, comfortable ride, and luxurious interior. The diesel engine’s fuel efficiency was a significant selling point, particularly in Europe where diesel fuel was more affordable than gasoline. Compared to the S 500, the 400 CDI offered a more economical alternative without sacrificing too much performance. However, some critics noted that the diesel engine was slightly noisier than the gasoline counterpart. Reliability was generally good, although the complex common rail injection system required careful maintenance.
Legacy
The Mercedes-Benz S 400 CDI Long (V220) remains a sought-after vehicle among enthusiasts and collectors. The OM 628 engine is known for its durability and longevity, provided it receives regular maintenance. While finding well-maintained examples can be challenging due to their age, these cars offer a unique combination of luxury, performance, and fuel efficiency. The V220 generation S-Class, and particularly the 400 CDI variant, represents a high point in Mercedes-Benz engineering and design, and continues to be appreciated for its refinement and build quality.
