🏷️ Basic Information

Make:

Mercedes-Benz

Model:

W126

Generation:

First Generation (1979-1991)

Body Styles:

SE (Coupé), SEL (Long-wheelbase Coupé), SD (Diesel Sedan), SDL (Long-wheelbase Diesel Sedan), SE (Sedan), SEL (Long-wheelbase Sedan), 500 SEC (Coupé), 560 SEC (Coupé), 560 SEL (Long-wheelbase Sedan)

Chassis Code:

W126

👋 Introduction

Model Segment:

Full-size Luxury Sedan and Coupé

Target Audience:

Affluent individuals seeking high-quality, reliable, and comfortable transportation with a focus on engineering and prestige.

Key Competitors:

BMW 7 Series (E23, E32), Jaguar XJ-S, Rolls-Royce Silver Spirit, Cadillac Eldorado, Lincoln Continental Mark VII.

Distinguishing Features:

Exceptional build quality, comfortable ride, advanced safety features for its era, sophisticated engineering, elegant styling, and strong brand reputation.

Manual Key Feature 1:

Comprehensive coverage exceeding factory manuals in accessibility and cost.

Manual Key Feature 2:

PDF format for easy viewing, searching, and selective printing.

Manual Key Feature 3:

Direct email delivery, eliminating shipping delays and costs.

Manual Key Feature 4:

Compatibility with all PC-based Windows operating systems and Mac.

📋 Manual Details

Systems Covered List:

Estimated Page Count:

Likely extensive, typical of factory-level workshop manuals (1000+ pages)

Manual Type:

Workshop Service / Repair Manual

Language:

English

Format:

PDF

📖 Manual Coverage

Engine Systems:

Engine disassembly, assembly, troubleshooting, performance tuning, cylinder head, block, pistons, connecting rods, crankshaft, camshafts, valve train, lubrication, cooling system components (radiator, water pump, thermostat, fan clutch), fuel injection system (Bosch K-Jetronic/KE-Jetronic), ignition system, emission control systems (EGR, catalytic converters).

Transmission Systems:

Automatic transmission overhaul (e.g., 722.3, 722.4, 722.5), manual transmission (less common), clutch service, driveshaft, differential, axle shafts.

Chassis Systems:

Front and rear suspension (independent, multi-link), shock absorbers, springs, control arms, ball joints, tie rods, power steering system, brake system (disc brakes front and rear, ABS components, hydraulic lines, master cylinder, calipers, pads, rotors), wheel bearing service.

Electrical Systems:

Complete wiring diagrams for all vehicle systems, starter motor, alternator, battery, lighting systems (headlights, taillights, interior), instrument cluster, gauges, switches, relays, fuses, power windows, power seats, central locking, climate control electronics, SRS airbag system (if applicable to specific models covered).

Body Systems:

Body panel removal and installation, doors, hood, trunk, bumpers, glass replacement, interior trim, convertible top mechanisms (if applicable to SEC models), structural repairs, rust prevention and repair.

Maintenance Procedures:

Oil changes, filter replacements, fluid level checks and top-offs, coolant flushes, spark plug replacement, belt inspections and replacement, brake fluid flush, air filter replacement, battery maintenance.

Repair Procedures:

Detailed step-by-step instructions for component removal, repair, and reinstallation for all major vehicle systems. Includes engine rebuilds, transmission overhauls, suspension component replacement, brake system repairs, electrical troubleshooting, and bodywork.

Troubleshooting Diagnostics:

Systematic diagnostic procedures, fault code interpretation (if applicable), common problem identification and solutions, electrical circuit testing, mechanical component testing.

Depth Of Coverage:

Comprehensive, covering everything from routine maintenance to complete engine and transmission overhauls. Suitable for professional mechanics and advanced DIY enthusiasts. Includes detailed torque specifications, clearances, and special tool requirements.

📊 Manual Specifications

File Format Type:

PDF (Portable Document Format)

Searchability:

Likely searchable text (OCR optimized) for efficient information retrieval.

Printable Quality:

High-quality, allowing for clear printing of text, diagrams, and photographs.

Print Flexibility:

Allows printing of all pages, specific sections, or individual pages as needed.

Binding Type:

N/A (Digital Delivery - Email)

Paper Type:

N/A (Digital Delivery - Email)

⚙️ Engine Specifications

Engine Variants Offered:

2.8L Inline-6 (M110), 3.0L Inline-6 Diesel (OM617), 3.8L V8 (M116), 4.2L V8 (M116), 5.0L V8 (M117), 5.6L V8 (M117).

Typical Horsepower Range:

140 hp (Diesel) to 240 hp (5.6L V8)

Typical Torque Range:

180 lb-ft (Diesel) to 330 lb-ft (5.6L V8)

Fuel Injection Systems:

Bosch K-Jetronic (CIS) and KE-Jetronic (CIS-E) for gasoline engines, mechanical injection for diesel engines.

Block Material:

Cast Iron (Inline-6 and V8)

Cylinder Head Material:

Aluminum Alloy

🔧 Transmission

Standard Transmission Type:

4-speed Automatic (e.g., 722.3, 722.4)

Optional Transmission Type:

5-speed Automatic (722.5 - on later models, e.g., 560 models), 4-speed Manual (rare, early models)

Torque Converter Lockup:

Available on certain automatic transmissions for improved fuel economy.

Automatic Transmission Fluid Type:

MB 236.1 or equivalent (e.g., Dexron II)

📐 Dimensions

Wheelbase Sedan:

116.1 inches (2950 mm)

Wheelbase Coupe:

112.2 inches (2850 mm)

Length Sedan:

197.4 inches (5015 mm)

Length Coupe:

194.5 inches (4940 mm)

Curb Weight Range:

Approximately 3,600 - 4,200 lbs (1630 - 1905 kg), depending on engine and body style.

🛡️ Safety Features

Crash Safety Design:

Engineered for superior safety with crumple zones and a reinforced passenger cell. Advanced for its time.

Available ABS:

Anti-lock Braking System (ABS) was an available option.

Standard Airbags:

Driver's side airbag became standard in later production years. Passenger airbag available on some models.

Seatbelts:

Designed with advanced seatbelt systems, including early forms of pre-tensioners and height adjustability.

💡 Technology Features

Original Infotainment:

Analog radio (often with cassette player), power antenna, basic sound systems. Later models offered digital climate control and premium sound options.

Early Driver Assistance:

Cruise control, power steering, ABS (on select models).

Original Connectivity:

Limited to basic antenna and speaker connections. No modern Bluetooth or USB integration from factory.

🔧 Maintenance

Oil Change Interval:

Typically every 5,000 - 7,500 miles (8,000 - 12,000 km) or 6-12 months, depending on driving conditions and oil type.

Major Service Interval:

Significant services involving spark plugs, coolant, brake fluid, and transmission fluid typically around 30,000 - 60,000 miles (50,000 - 100,000 km).

Engine Oil Spec:

API SG or higher, SAE 10W-30 or 15W-40 recommended (check manual for specific viscosity and MB approval)

Coolant Spec:

Mercedes-Benz approved coolant (e.g., G05 or G48), typically a 50/50 mix with distilled water.

Brake Fluid Spec:

DOT 3 or DOT 4

Common Issue 1:

Headliner sagging (fabric detaches from backing).

Common Issue 2:

Biodegradable wiring insulation failures (especially in loom harness), leading to electrical gremlins.

Common Issue 3:

Fuel distributor and pump issues (K-Jetronic system).

Common Issue 4:

Vacuum hose degradation and leaks affecting climate control, central locking, and engine performance.

Common Issue 5:

Door lock actuators and central locking system failures.

📚 Vehicle History

Mercedes Benz Philosophy:

Pioneering automotive engineering, focus on durability, safety, and luxury ('The Best or Nothing').

Predecessor:

W116 S-Class

Successor:

W140 S-Class

Production Years:

1979-1991

Manufacturing Locations:

Germany (Sindelfingen)

🏆 Awards & Recognition

Industry Recognition:

Consistently ranked among the best luxury sedans of its era for comfort, engineering, and safety. Praised for its quiet ride and robust construction.

Design Awards:

Often cited for its timeless and elegant design, setting a benchmark for automotive aesthetics in the 1980s.

Safety Certifications:

Designed to meet and exceed global safety standards of its time, though specific official rating agencies and formats differed from modern NCAP ratings.