The Mercedes-Benz S 420 Long, produced between March 1994 and August 1995, represented a significant iteration of the W140 S-Class, specifically the facelifted model. Positioned as a high-end luxury sedan, the S 420 Long offered a longer wheelbase than the standard W140, providing increased rear passenger legroom – a key feature for markets prioritizing chauffeur-driven transport. This variant occupied a sweet spot in the S-Class lineup, offering substantial performance from its V8 engine while maintaining the renowned Mercedes-Benz comfort and refinement. It sat above the S 320 and below the flagship S 500 and S 600 models in terms of price and performance.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | S-class |
| Generation | S-class Long (V140, facelift 1994) |
| Type (Engine) | S 420 V8 (279 Hp) 4G-TRONIC |
| Start of production | March, 1994 |
| End of production | August, 1995 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 16 l/100 km (14.7 US mpg, 17.7 UK mpg, 6.3 km/l) |
| Fuel consumption (extra urban) | 9.7-11.7 l/100 km (24.2 – 20.1 US mpg, 29.1 – 24.1 UK mpg, 10.3 – 8.5 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 8.3 sec |
| Acceleration 0 – 62 mph | 8.3 sec |
| Acceleration 0 – 60 mph | 7.9 sec |
| Maximum speed | 245 km/h (152.24 mph) |
| Weight-to-power ratio | 7.2 kg/Hp, 139.5 Hp/tonne |
| Weight-to-torque ratio | 5 kg/Nm, 200 Nm/tonne |
| Power | 279 Hp @ 5700 rpm |
| Power per litre | 66.5 Hp/l |
| Torque | 400 Nm @ 3900 rpm (295.02 lb.-ft. @ 3900 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 119.971 |
| Engine displacement | 4196 cm3 (256.06 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 92 mm (3.62 in.) |
| Piston Stroke | 78.9 mm (3.11 in.) |
| Compression ratio | 11:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Coolant | 16.5 l (17.44 US qt | 14.52 UK qt) |
| Kerb Weight | 2000 kg (4409.25 lbs.) |
| Max. weight | 2650 kg (5842.25 lbs.) |
| Max load | 650 kg (1433 lbs.) |
| Trunk (boot) space – minimum | 525 l (18.54 cu. ft.) |
| Fuel tank capacity | 100 l (26.42 US gal | 22 UK gal) |
| Length | 5213 mm (205.24 in.) |
| Width | 1886 mm (74.25 in.) |
| Height | 1486 mm (58.5 in.) |
| Wheelbase | 3140 mm (123.62 in.) |
| Front track | 1606 mm (63.23 in.) |
| Rear (Back) track | 1579 mm (62.17 in.) |
| Minimum turning circle | 12.51 m (41.04 ft.) |
| Drivetrain Architecture | Rear wheel drive |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 4 gears, automatic transmission G-TRONIC |
| Front suspension | Coil spring, Double wishbone, Transverse stabilizer |
| Rear suspension | Independent multi-link suspension, Transverse stabilizer, Coil spring |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Power steering | Hydraulic Steering |
| Tires size | 235/60 R16 |
| Wheel rims size | 7.5J x 16 |
Powertrain & Engine Architecture
The heart of the S 420 Long was the M119.971 4.2-liter V8 engine. This engine, a cornerstone of Mercedes-Benz’s engineering prowess, featured a 90-degree V-angle, all-aluminum construction, and a dual overhead camshaft (DOHC) valvetrain with four valves per cylinder. The M119 utilized Bosch Motronic engine management and multi-port fuel injection, delivering smooth and responsive power. The 4G-TRONIC automatic transmission, a four-speed unit, was specifically calibrated to complement the V8’s torque curve, prioritizing smooth shifts and comfortable cruising. This transmission, while not as technologically advanced as later iterations, was known for its durability and reliability.
Driving Characteristics
The S 420 Long offered a distinctly different driving experience compared to its more performance-oriented siblings like the S 500. While the 279 horsepower and 295 lb-ft of torque provided ample power for effortless highway cruising and confident overtaking, it wasn’t designed for aggressive driving. The 4G-TRONIC transmission, while smooth, had relatively widely spaced gear ratios, meaning the engine didn’t always feel as responsive as it could. Compared to a manual transmission equipped S-Class, the automatic dulled the immediacy of the engine’s power delivery. However, for the target audience – those prioritizing comfort and a relaxed driving experience – this was often considered a benefit. The longer wheelbase contributed to a more stable and composed ride, particularly at higher speeds.
Equipment & Trim Levels
The S 420 Long came standard with a comprehensive array of luxury features. Leather upholstery was standard, along with power-adjustable front seats with memory function. Climate control, a premium sound system, and power windows and locks were also included. The wood trim throughout the cabin added to the sense of opulence. Optional extras included a rear seat entertainment system, upgraded leather, a sunroof, and various driver assistance features. The “Long” designation meant extended rear legroom, often paired with power-adjustable rear seats and individual climate controls for rear passengers.
Chassis & Braking
The W140 S-Class featured a sophisticated chassis design. The S 420 Long utilized a double-wishbone front suspension and an independent multi-link rear suspension, both incorporating coil springs and anti-roll bars. This setup provided a comfortable and controlled ride. Braking duties were handled by ventilated disc brakes on all four wheels, coupled with an Anti-lock Braking System (ABS) for enhanced safety. The suspension was tuned to prioritize ride comfort over outright handling sharpness, reflecting the car’s luxury positioning.
Market Reception & Comparison
The S 420 Long was generally well-received by automotive critics. It was praised for its luxurious interior, comfortable ride, and refined engine. However, some reviewers noted that the 4G-TRONIC transmission could feel a bit dated compared to newer automatic transmissions. Compared to the S 320, the S 420 offered a noticeable performance upgrade. Against the S 500, it provided a more balanced combination of performance and fuel economy. Fuel economy, while not a primary concern for S-Class buyers, was respectable for a V8-powered luxury sedan of its size.
Legacy
The M119 engine, found in the S 420, is renowned for its durability and longevity. With proper maintenance, these engines can reliably exceed 200,000 miles. The 4G-TRONIC transmission, while not as sophisticated as modern automatics, is also generally considered robust. Today, the W140 S-Class, including the S 420 Long, is gaining recognition as a modern classic. Well-maintained examples are sought after by collectors and enthusiasts who appreciate their build quality, luxurious features, and timeless design. The S 420 Long represents a high point in Mercedes-Benz engineering and a testament to the brand’s commitment to luxury and refinement.
