Mercedes-Benz , S-Class , W126 , 300 SD (1979-1985)

Design and Features:

• The W126 S-Class was a full-size luxury sedan that debuted in 1979 and continued until 1991.
• The 300SD model, introduced in 1979, featured a more streamlined exterior design compared to its predecessors.
• Its dimensions were 523.5 cm (20.6 inches) wide, 198.7 cm (7.8 inches) tall, and 515.2 cm (20.3 inches) long.
• The vehicle had a wheelbase of 312.4 cm (12.3 inches), offering ample space for passengers and cargo.

Engine and Performance:

• The 300SD was powered by a 3.0-liter inline-six diesel engine, producing 122 kW (165 bhp).
• This turbocharged SD-series engine featured a four-valve-per-cylinder design, with dual overhead camshafts.
• The transmission offered in the 300SD was a five-speed manual or an optional four-speed automatic unit.
• A rear differential and axle setup provided stable power delivery to the wheels.

Interior and Comfort:

• Inside, the 300SD featured opulent appointments, including soft-touch materials, wood trim accents, and spacious seating for up to five passengers.
• The front seats were adjustable, ensuring optimal comfort levels for drivers. Rear passengers also enjoyed ample legroom, with their own separate heating and ventilation controls.

Technology and Safety:

• Anti-lock braking system (ABS) became an available feature in the 1985 model year.
• In addition to this advanced safety feature, Mercedes-Benz implemented other cutting-edge technologies such as traction control systems (TCR-1).
• The onboard electronic features included a basic navigation system called "Daimler-Chrysler's Map Navigation System", an optional hands-free phone system, and cruise control.

Suspension, Brakes, and Tires:

• The 300SD utilized a dual wishbone setup with MacPherson struts at the front axle for enhanced handling.
• Rear semi-trailing arms with coil springs helped absorb road imperfections and provide stability under heavy loads.
• Its braking system incorporated ventilated discs in the front and solid units in the rear.
• High-quality Michelin 225/70R15 PAX tires offered improved traction, stability, and comfort.

Dimensions and Curb Weight:

• The vehicle's curb weight reached approximately 2,160 kg (4,762 pounds) for models without air suspension.
• When equipped with it, the curb weight rose to around 2,310 kg (5,078 pounds).
• The overall height was 1,987 cm (78.3 inches), while its length and width measured 515.2 cm (20.3 inches) and 523.5 cm (20.6 inches), respectively.

Warranty and Maintenance:

• Buyers could purchase a four-year, unlimited mileage warranty for their vehicle.
• Regular maintenance requirements were relatively low compared to other luxury cars of its time due to the robust build quality of Mercedes-Benz's W126 platform.

Market Positioning and Sales:

• As one of the top-tier vehicles offered by Mercedes-Benz during this period, the S-Class range (including the 300SD) was positioned in a premium market niche.
• It competed directly with other high-end luxury sedans such as BMW's E28 M5 and various Rolls-Royce models.

Legacy:

• The W126 chassis proved highly reliable and robust throughout its production run, gaining a strong reputation for durability among owners.
• Although the 300SD model was primarily focused on comfort and efficiency rather than outright performance, it set new standards in diesel-powered luxury vehicles.