🏷️ Basic Information

Make:

Mercedes-Benz

Model:

300 D Turbo

Model Code:

W124 (specific chassis designations vary for diesel models, e.g., 124.130)

Product Name:

Mercedes 300 D Turbo 1986-1987 Service Repair Manual Download

Generation:

First Generation W124 E-Class (Diesel Variant)

Engine Code:

OM603.960 (3.0L Turbocharged Diesel Inline-5)

👋 Introduction

Market Position:

The Mercedes-Benz 300 D Turbo represented a highly desirable, robust, and fuel-efficient luxury sedan in the mid-to-late 1980s. It was positioned as a premium diesel offering, known for its engineering quality, durability, and long-distance cruising capability, competing with other European luxury brands.

Competitive Analysis:

Competitors included diesel variants from brands like BMW (e.g., 524td), Audi, and potentially some larger American sedans that offered diesel options, though Mercedes often held a distinct advantage in perceived build quality and diesel powertrain refinement at the time.

Key Features:

Turbocharged diesel engine for improved performance over naturally aspirated versions, legendary W124 chassis engineering providing excellent ride and handling, robust build quality, luxurious interior appointments, and strong reputation for longevity and reliability.

📋 Manual Details

Years Covered:

1986, 1987

Models Covered:

Mercedes-Benz 300 D Turbo (Sedan/Saloon, potentially Coupe/Estate depending on specific chassis codes included, though description implies primary focus on the sedan)

Page Count Estimate:

Extensive, likely several hundred pages minimum per year or combined, based on detailed coverage list.

Manual Type:

Factory Service and Repair Manual

Language:

English (presumed based on product description and sales context)

Format:

PDF (Downloadable)

📖 Manual Coverage

Engine Systems:

Diesel fuel injection system (mechanical), turbocharging, cooling system, lubrication system, intake and exhaust systems, engine mounts, engine electricals (basic diagnostic checks for sensors relevant to engine operation).

Transmission Systems:

Manual transmission, Automatic transmission (e.g., 722.3 or 722.4 variants), transfer case (if applicable to specific chassis variant, though less common for the standard 300D Turbo sedan).

Drivetrain Systems:

Clutch system, front axle, rear axle, drive shaft flexible couplings, wheel hub inspection.

Suspension Steering Brakes:

Front and rear suspension components, ball joints, steering system (play, bolt tightening), brake system (fluid, lines, pads, discs, parking brake), power steering.

Electrical Lighting HVAC:

Basic electrical checks (warning lamps), lighting inspection (headlamps, exterior), HVAC system (filters, refrigerant charge, wiper/washer system).

Body Chassis:

Body structure inspection, water leakage and corrosion, suspension and body structure, door hinges/locks, sunroof, soft top (if applicable), hood lubrication, paint damage, noise encapsulation panels, lower engine panel.

Maintenance Procedures:

Engine oil and filter change, fuel filter replacement, air filter cleaning/replacement, V-belt inspection/tensioning, poly V-belt inspection, spark plug inspection/replacement (though spark plugs are irrelevant for a diesel, this likely points to general tune-up items that the manual may cover broadly for the W124 range, or it's an oversight in the product description's broad list), valve clearance adjustment/checking, idle speed adjustment, injection timing adjustment.

Repair Procedures:

Replacement of major components (e.g., filters, sensors, belts, fluids), adjustment of various systems (e.g., parking brake, injection timing), fluid level checks and corrections for all major driveline and chassis components, fuel system checks, cooling system maintenance.

Diagnostic Procedures:

Inspection of component condition, lines and hoses, suspension and body structure, water leakage and corrosion, checking valve clearance, checking injection timing, checking condition and tension of V-belts, checking intake & exhaust manifold seating, checking warning & indicator lamps.

Technical Depth:

Comprehensive factory-level detail, suitable for professional technicians and advanced DIY enthusiasts. Covers routine maintenance, troubleshooting, and repair procedures for all major vehicle systems.

📊 Manual Specifications

File Format:

PDF

Print Quality:

High Resolution, Printable (stated as 'real files not scans')

Binding Type:

N/A (Digital Download)

Paper Type:

N/A (Digital Download)

Searchability:

Fully searchable text content

Bookmarking:

Completely bookmarked for easy navigation

⚙️ Engine Specifications

Engine Type:

Inline 5-Cylinder Turbocharged Diesel

Displacement:

2.999 liters (3.0L)

Bore X Stroke:

87.0 mm x 84.0 mm (typical for OM603)

Compression Ratio:

22.0:1 (typical for OM603)

Horsepower:

Approx. 143-148 hp @ 4600 rpm (varies slightly by market/tuning)

Torque:

Approx. 237 lb-ft (320 Nm) @ 2400 rpm (typical for OM603.960)

Fuel System Type:

Bosch Inline Mechanical Fuel Injection Pump with Turbocharger and Intercooler

Fuel Type:

Diesel Fuel

Engine Mounts:

Hydraulic engine mounts for vibration isolation

Valve Train:

Single Overhead Camshaft (SOHC), 2 valves per cylinder (10 valves total)

🔧 Transmission

Transmission Type:

4-speed Automatic Transmission (typically 722.3 or 722.4)

Transmission Type Optional:

5-speed Manual Transmission (less common for the 300D Turbo in many markets, but available)

Automatic Transmission Features:

Lock-up torque converter, hydraulic control

📐 Dimensions

Length:

Approx. 4740 mm (186.6 in) for sedan

Width:

Approx. 1740 mm (68.5 in) for sedan

Height:

Approx. 1430 mm (56.3 in) for sedan

Curb Weight:

Approx. 1500-1600 kg (3300-3500 lbs), depending on options and transmission

Gross Vehicle Weight Rating:

Approx. 2050 kg (4519 lbs)

🛡️ Safety Features

Safety Ratings:

While formal crash test ratings like modern NCAP did not exist in the same way, the W124 chassis was renowned for its structural integrity, safety cell design, and passive safety features for its era.

Active Safety Features:

ABS (Anti-lock Braking System) was often optional or standard on higher trims/later models within this range. Power-assisted steering for improved control.

Passive Safety Features:

Reinforced passenger compartment, energy-absorbing steering column, driver's airbag (often optional), seat belts with pretensioners.

💡 Technology Features

Infotainment Features:

Basic analog radio/cassette player. Advanced infotainment systems were not present in the modern sense. Manual covers cleaning of cassette deck tone head.

Driver Assistance Features:

ABS (as mentioned, often optional), Level Control (Hydraulic), ADS (Active Damping System), ASD (Automatic Slip Differential), 4MATIC (All-Wheel Drive) were optional features on some W124 models and may be covered in comprehensive manuals.

Connectivity:

No modern connectivity features (Bluetooth, USB, etc.). Antenna mast cleaning is mentioned.

🔧 Maintenance

Oil Change Interval:

Typically every 7,500-10,000 miles (12,000-16,000 km) or annually, whichever comes first, depending on driving conditions and oil used. The manual will provide definitive factory recommendations.

Fuel Filter Interval:

Recommended replacement every 15,000-20,000 miles (24,000-32,000 km) or as per manual specifications, critical for diesel longevity.

Air Filter Interval:

Inspection at oil changes, replacement typically every 15,000-20,000 miles (24,000-32,000 km) or as needed based on operating environment.

Engine Oil Specification:

API CD or higher, SAE 15W-40 or 10W-40 depending on climate (manual will specify exact MB approval).

Coolant Specification:

Proprietary Mercedes-Benz coolant or equivalent, mixed 50/50 with distilled water. Manual will specify MB approval number.

Automatic Transmission Fluid:

MB Spec 236.1 or 236.3 ATF (Dexron II compatible for some variants, manual is crucial for exact spec).

Brake Fluid Specification:

DOT 3 or DOT 4.

Known Issues:

Diesel specific: Glow plug issues, injector problems, potential for head gasket leaks (though less common than gasoline variants), fuel system leaks, turbocharger wear. General W124: Suspension component wear (bushings, ball joints), wiring harness insulation degradation (especially in older models), AC system leaks, rust in common W124 areas (wheel arches, window seals).

📚 Vehicle History

Brand Heritage:

Mercedes-Benz has a long and storied history of producing robust, technologically advanced, and luxurious vehicles, with a particular strength in diesel engine technology and engineering excellence.

Model Evolution:

The W124 generation (1984-1995) is celebrated as one of Mercedes-Benz's finest designs, known for its exceptional build quality, durability, and engineering. The 300 D Turbo was a key variant, offering a blend of performance and fuel economy in the mid-size luxury sedan segment.

Production Years W124:

1984-1995 (Sedan/Saloon)

Production Location:

Various Mercedes-Benz plants, primarily in Germany.

🏆 Awards & Recognition

Recognitions:

The W124 platform as a whole received widespread acclaim from automotive journalists and owners for its build quality, engineering, and longevity, often cited as one of the best Mercedes-Benz models ever produced.