🏷️ Basic Information

Make:

Mercedes-Benz

Model:

380SEL

Chassis Code:

W126

Generation Code:

W126 (First Generation)

Model Code:

380SEL

👋 Introduction

Vehicle Class:

Full-size Luxury Sedan

Target Audience:

Affluent individuals seeking a comfortable, well-engineered, and prestigious European luxury automobile.

Key Competitors:

BMW 7 Series (E23), Audi V8, Jaguar XJ-S (though a coupe), Cadillac Eldorado/Seville (US market competitor).

Design Philosophy:

Understated elegance, exceptional build quality, advanced engineering for its time, and uncompromising comfort.

Manual Value Proposition:

Provides professional-grade service information identical to what authorized Mercedes-Benz dealerships utilize, empowering owners and independent mechanics for accurate and efficient maintenance and repair.

📋 Manual Details

Primary Coverage:

Service and Repair for Mercedes-Benz 380SEL (W126)

Model Years Covered:

1981, 1982, 1983

Estimated Page Count:

Extensive (Factory Original - typically 1000+ pages across multiple volumes, though digital format may vary)

Type:

Factory Workshop Service Repair Manual

Language:

English

Digital Format:

HTML/Flash menu with PDF files

📖 Manual Coverage

Engine Mechanical:

Complete engine overhaul, cylinder head, block, pistons, crankshaft, camshafts, valve train, lubrication system, cooling system, fuel injection system (Bosch K-Jetronic), emissions control.

Engine Electrical:

Ignition system, starter system, charging system (alternator), engine control unit (ECU), sensor diagnostics, wiring diagrams.

Transmission:

Automatic transmission service and repair (e.g., 3-speed or 4-speed automatic depending on specific production), torque converter, hydraulic system, electronic controls (if applicable).

Brakes:

Hydraulic brake system, disc brakes (front and rear), ABS (Anti-lock Braking System) diagnostics and repair, brake fluid specifications, brake component replacement (pads, rotors, calipers).

Suspension:

Front and rear suspension components, shock absorbers, springs, control arms, bushings, steering linkage, wheel alignment specifications.

Steering:

Power steering system, steering gear, steering column, tie rods, power steering fluid specifications.

Body And Chassis:

Body panel repair, rust prevention, door mechanisms, window regulators, sunroof operation, bumpers, exterior trim, interior trim, seats, headliner, sound deadening.

Electrical System:

Lighting system (headlights, taillights, interior), battery, starter, alternator, fuses, relays, wiring diagrams for all vehicle systems, power windows, power seats, central locking, climate control system.

Climate Control:

Air conditioning system (compressor, evaporator, condenser, refrigerant), heating system, blower motor, HVAC controls, climate control panel.

Fuel System:

Fuel tank, fuel pump, fuel lines, fuel filter, fuel pressure regulator, Bosch K-Jetronic fuel injection system troubleshooting and adjustment.

Exhaust System:

Exhaust manifolds, catalytic converter, mufflers, exhaust pipes, hangers.

Wheels And Tires:

Tire pressure specifications, wheel bolt patterns, wheel bearing replacement.

Maintenance:

Routine maintenance schedules, oil changes, filter replacements (oil, fuel, air), spark plug replacement, fluid level checks and top-offs, lubrication points.

Diagnostics:

Troubleshooting guides for common problems, diagnostic procedures for engine, transmission, brakes, and electrical systems, fault code interpretation (if applicable).

Repair:

Step-by-step repair instructions for all major vehicle components, including engine rebuilds, transmission overhauls, brake system repairs, suspension component replacement, electrical component repair, body panel repair.

Replacement:

Detailed procedures for replacing parts such as belts, hoses, gaskets, seals, wear items, and major components.

Adjustment:

Procedures for adjusting engine timing, fuel mixture (K-Jetronic), idle speed, parking brake, etc.

Depth:

Comprehensive: Covers everything from basic owner maintenance to complete engine and transmission rebuilds, including detailed diagnostic procedures and schematics.

Documentation Style:

Factory level detail, including torque specifications, clearances, tolerances, and diagnostic charts.

📊 Manual Specifications

Format Details:

HTML/Flash menu provides navigation to individual PDF files, allowing for organized access to specific sections. PDF files are generally searchable and printable.

Print Quality Digital:

High (as dictated by original factory scans/digitalization, typically clear text and diagrams).

Binding Type Digital:

N/A (Digital Format)

Paper Type Digital:

N/A (Digital Format)

Operating Systems:

Windows (95, 98, ME, XP, Vista, 7), Linux, macOS

⚙️ Engine Specifications

Engine Code:

M116

Configuration:

3.8-liter (3839 cc) V8

Valvetrain:

SOHC (Single Overhead Camshaft) per bank, 2 valves per cylinder

Horsepower Approx:

155-160 hp (SAE Net) at approximately 4750-5000 RPM (varies slightly by year and market)

Torque Approx:

210-220 lb-ft (SAE Net) at approximately 2500-3000 RPM (varies slightly by year and market)

Injection System:

Bosch K-Jetronic (CIS - Continuous Injection System), mechanical fuel injection

Fuel Type:

Unleaded Gasoline

Coolant Type:

Mercedes-Benz Specification Coolant (e.g., G48 or equivalent)

Oil Type:

API SF/SG or higher, SAE 15W-40 or 10W-40 (check manual for specific viscosity recommendations based on climate)

Oil Capacity Approx:

7.5 liters (7.9 US quarts) with filter change

🔧 Transmission

Type:

4-speed Automatic Transmission (e.g., 4G-TRONIC, 722.3 series)

Type:

No manual transmission option typically available for 380SEL in these years.

Gear Selection:

P, R, N, 3, 4 (later models may have D)

Fluid Type:

MB Spec 236.1 Automatic Transmission Fluid (e.g., Dexron II or equivalent as per manual)

Fluid Capacity Approx:

2.5 - 3.0 liters (2.6 - 3.2 US quarts) for torque converter and lines; 8.0 liters (8.5 US quarts) total capacity

📐 Dimensions

Length Approx:

5088 mm (199.9 inches)

Width Approx:

1798 mm (70.8 inches)

Height Approx:

1430 mm (56.3 inches)

Wheelbase Approx:

3075 mm (121.1 inches)

Curb Weight Approx:

1700 - 1800 kg (3748 - 3968 lbs)

Gross Vehicle Weight Rating Approx:

2250 kg (4960 lbs)

🛡️ Safety Features

Crash Test Information:

While specific official crash test ratings from agencies like NHTSA or IIHS for this era are limited or non-existent in modern formats, the W126 chassis was engineered with advanced safety features for its time, including a high-strength safety cage and crumple zones.

ABS:

Anti-lock Braking System (ABS) standard on most models

Traction Control:

Optional or available on later production within this range, though less sophisticated than modern systems.

Airbags:

Driver's airbag was an option, becoming more common towards the end of the W126's lifecycle. Passenger airbags were generally not available until later W140 generation.

Seatbelts:

3-point inertia-reel seatbelts front and rear, often with pre-tensioners.

Structure:

Reinforced passenger cell, energy-absorbing steering column.

💡 Technology Features

Audio System:

Factory fitted Becker or Blaupunkt radio/cassette players were common. Features would typically include AM/FM stereo, cassette playback, and power antenna control. Digital displays for tuning/volume were advanced for the era.

Navigation:

No integrated navigation systems. This was an era before widespread automotive GPS.

Cruise Control:

Standard or optional on most models, providing speed regulation.

Automatic Climate Control:

Available, offering programmable temperature settings and fan speeds.

Connectivity Features:

No modern connectivity features like Bluetooth or USB. Communication systems were limited to the in-car entertainment.

🔧 Maintenance

Oil Change Interval:

Typically every 10,000 - 15,000 km (6,000 - 9,000 miles) or 12 months, whichever comes first. Refer to the manual for exact specifications.

Transmission Fluid Service:

Every 50,000 - 80,000 km (30,000 - 50,000 miles), including filter change. Crucial for longevity.

Air Filter Replacement:

Every 20,000 - 30,000 km (12,000 - 18,000 miles).

Fuel Filter Replacement:

Every 30,000 - 40,000 km (18,000 - 25,000 miles).

Spark Plug Replacement:

Every 40,000 - 60,000 km (25,000 - 37,000 miles), depending on plug type.

Coolant Spec:

Mercedes-Benz Specification Coolant (e.g., G48) or equivalent ethylene glycol-based coolant with corrosion inhibitors.

Brake Fluid Spec:

DOT 3 or DOT 4 brake fluid (ensure it's from a sealed container).

Power Steering Fluid Spec:

Mercedes-Benz Specification Power Steering Fluid or Dexron II/III ATF (check manual for specific recommendation).

Common Wear Items:

Rubber bushings (suspension, exhaust), climate control O-rings and seals, vacuum lines (affecting various systems), fuel accumulator, wiring harness brittle points, idle control valve (on some models).

K Jetronic Sensitivity:

The K-Jetronic fuel system, while robust, requires precise maintenance and can be sensitive to fuel quality, clogged filters, and aging components like the frequency valve and airflow meter.

Temperature Control Issues:

Can include HVAC blower motor issues, blend door actuator failures, or refrigerant leaks due to age.

📚 Vehicle History

Legacy:

Mercedes-Benz has a long-standing reputation for engineering excellence, safety, and luxury spanning over a century. The W126 represented a pinnacle of this tradition in the sedan segment.

W126 Introduction:

The W126 S-Class was introduced in 1979 as the successor to the W116. It was a significant evolution, offering improved aerodynamics, safety, and a more refined driving experience.

380Sel Variant:

The 380SEL designation refers to the long-wheelbase version ('L' for Lang) powered by the 3.8-liter V8 engine. It was a popular choice for its blend of performance and spaciousness.

Production Years:

W126 production spanned from 1979 to 1991. The 380SEL model specifically within this range covers 1981-1985 model years (with the 3.8L V8 phased out for larger displacement engines later).

Manufacturing Location:

Primarily Stuttgart, Germany.

🏆 Awards & Recognition

Design Awards:

While specific awards for the 380SEL are not prominently documented, the W126 generation as a whole was widely recognized for its benchmark styling, safety, and engineering by automotive journalists and critics worldwide.

Reliability Perception:

The W126 generation is often regarded as one of the most reliable and well-built Mercedes-Benz models of its era, known for its durability when properly maintained. The 3.8L V8 engine, while not as powerful as later iterations, is generally considered robust.

Certification Standards:

Vehicles of this era adhered to prevailing safety and emissions standards of the time for their respective markets (e.g., Federal Motor Vehicle Safety Standards in the US, ECE regulations in Europe).