🏷️ Basic Information

Make:

Mercedes-Benz

Model:

300D 2.5 Turbo

Chassis Code:

W124 (E-Class)

Engine Code Family:

OM602.912

Engine Displacement Liters:

2.5

Engine Type:

Inline-5 Cylinder Diesel Turbocharged

Generation Name:

Second Generation W124

Generation Years:

1984-1995 (W124)

👋 Introduction

Vehicle Segment:

Executive Sedan/Saloon (E-Class)

Competitors:

BMW 5 Series (E34), Audi 100/200, Volvo 740/760, Saab 9000, Jaguar XJ6

Vehicle Strengths:

Renowned Mercedes-Benz build quality, durability, diesel engine efficiency and longevity, comfortable ride, strong safety features for its era.

Target Audience Benefit:

Provides essential, factory-level technical information for maintaining, troubleshooting, and repairing the Mercedes-Benz 300D 2.5 Turbo across multiple model years, ensuring proper upkeep and longevity of a classic vehicle.

📋 Manual Details

Covered Years:

1990, 1991, 1992, 1993

Estimated Page Count:

Varies by year, typically 500-1000+ pages per year

Manual Type:

Service and Repair Manual

Language:

English

Format:

Digital (PDF / WINRAR)

📖 Manual Coverage

Engine Mechanical:

Engine assembly, disassembly, rebuilding, timing, lubrication, cooling system, fuel system (injection, filters, pre-filters)

Engine Electrical:

Ignition system (spark plugs), starter system, charging system, warning lamps, diagnostic codes (where applicable)

Transmission:

Manual transmission oil change, checking fluid levels; Automatic transmission fluid and filter change, checking fluid levels

Drivetrain:

Transfer case fluid change and checking levels, front axle oil level checking, rear axle oil change and checking levels, drive shaft flexible coupling inspection

Suspension Steering:

Suspension and body structure inspection, self-leveling suspension inspection, level control (ADS, ASD, 4MATIC) fluid level, front axle ball joints checking, rear axle mount adjustment

Brakes:

Brake fluid level checking, brake lines inspection, brake pads and disk thickness inspection, brake fluid replacement, parking brake adjustment and check, brake disk cleaning

Body Chassis:

Water leakage and corrosion inspection, wheel inspection and rotation, tire pressure correction, wheel bolt tightening, door hinge lubrication, door lock lubrication, hood lubrication, body paint damage inspection

HVAC:

Cooling and heating system checks, dust filter replacement, active charcoal filter replacement, recirculating air filter replacement, AC refrigerant charge check

Electrical Body:

Headlamp and exterior lamp inspection, windshield wiper and washer inspection, antenna mast cleaning, sunroof cleaning and greasing, hydraulic top fluid level check

Routine Maintenance:

Engine oil and filter change, air filter replacement, V-belt condition checks, fuel filter replacement, spark plug inspection/replacement, fluid level checks (coolant, power steering, brake, washer), battery fluid check

Engine Repair:

Valve clearance adjustment, idle speed adjustment, injection timing adjustment, intake/exhaust manifold seating check, oxygen sensor replacement

Drivetrain Maintenance:

Fluid changes for manual and automatic transmissions, transfer case, front and rear axles

Chassis Repair:

Ball joint inspection, steering play check, suspension component checks, brake component checks and adjustments

Bodywork Care:

Corrosion inspection, water leak diagnosis, lubrication of moving parts, cleaning of specific components (e.g., cassette deck tone head, sunroof rails)

Depth Of Coverage:

Comprehensive: Covers basic maintenance to major component repair and rebuilding. Includes diagnostic procedures for troubleshooting.

Intended User:

Professional mechanics and experienced DIY enthusiasts

📊 Manual Specifications

File Type:

PDF, WINRAR archive

Searchability:

Likely searchable text within PDFs, depending on the source scan quality

Digital Quality:

Varies based on original source; expect clear diagrams and text for factory-level documentation.

Binding Type:

N/A (Digital)

Paper Type:

N/A (Digital)

Operating Systems:

Win95/98/ME/XP/vista/7/8, Linux, MAC, iOS, Android

Delivery Method:

Instant Download

⚙️ Engine Specifications

Engine Code:

OM602.912

Engine Configuration:

Inline 5-cylinder, turbocharged diesel

Bore X Stroke Mm:

87.0 x 100.0

Compression Ratio:

22.0:1

Valvetrain:

SOHC (Single Overhead Camshaft), 2 valves per cylinder

Horsepower Ps Rpm:

126 PS (93 kW) @ 4600 rpm

Torque Nm Rpm:

230 Nm (169 lb-ft) @ 2400 rpm

Fuel Injection:

Mechanical Direct Injection with Bosch VE Rotary Pump and Turbocharger

Fuel Type:

Diesel

Engine Oil Capacity Liters:

7.0 (with filter)

🔧 Transmission

Transmission Type Standard:

5-speed Manual Transmission

Transmission Type Optional:

4-speed Automatic Transmission (4G-TRONIC)

Transmission Oil Manual Spec:

API GL-4, SAE 75W-85 or 75W-90 (refer to specific year manual for exact spec)

Transmission Oil Automatic Spec:

MB 236.6 (ATF Dexron II D or equivalent)

📐 Dimensions

Length Mm:

4740

Width Mm:

1740

Height Mm:

1430

Curb Weight Kg Manual:

~1550

Curb Weight Kg Automatic:

~1590

🛡️ Safety Features

Era Safety Features:

Designed with Mercedes-Benz's emphasis on passive safety: crumple zones, safety cage, padded interior. ABS was typically standard or optional.

Active Safety Systems:

Anti-lock Braking System (ABS), optional Traction Control (ASR) on some models

Passive Safety Features:

Front and rear crumple zones, safety steering column, reinforced passenger cell, seat belts with pre-tensioners (later models/options).

💡 Technology Features

Infotainment Systems:

Period-appropriate Becker or Clarion radio/cassette players, with options for CD changers. Antennas were often powered and mast-driven.

Driver Assistance Features:

ABS, optional traction control (ASR), automatic climate control (optional), self-leveling suspension (optional), automatic antenna, cruise control (optional).

Connectivity Features:

Limited by era; primarily related to radio functions and power antenna operation.

🔧 Maintenance

Oil Change Interval:

Typically every 10,000-15,000 km (6,000-9,000 miles) or annually, using synthetic diesel oil. Refer to manual for precise intervals and oil type.

Air Filter Replacement:

Check every 15,000-20,000 km (9,000-12,000 miles), replace as needed. Metal-reinforced elements can often be cleaned.

Fuel Filter Replacement:

Typically every 30,000-40,000 km (18,000-24,000 miles). Pre-filter should be checked and replaced more frequently if symptoms arise.

Coolant Replacement:

Every 2-3 years or as specified by coolant type (e.g., G48/G05). Check for antifreeze protection annually.

Engine Oil Specification:

API CG-4 or CH-4 (or equivalent diesel rated oil). Viscosity often 5W-40 or 10W-40. Consult manual for exact Mercedes-Benz specification (e.g., MB-Approval).

Power Steering Fluid:

MB 236.3 (ATF Dexron II D or Pentosin CHF 11 S, check manual for specific fluid type).

Brake Fluid:

DOT 3 or DOT 4 (ensure it's a quality synthetic brake fluid, replaced every 2 years due to moisture absorption).

Common Diesel Issues:

Glow plug failure, injector issues, turbocharger wear, vacuum line leaks, head gasket issues (less common on OM602 than early diesels), rust (especially around wheel arches, jacking points, under battery tray), climate control system faults (e.g., servo issues), vibration issues from engine mounts or driveshaft flex discs.

📚 Vehicle History

Mercedes Benz Legacy:

Pioneering automotive manufacturer with a long history of engineering excellence, innovation, and luxury vehicles, particularly known for diesel engine technology.

W124 E Class Lineage:

The W124 platform represented a significant evolution in Mercedes-Benz sedan design, known for its robust engineering, exceptional build quality, and technological advancements. The 300D 2.5 Turbo was a popular diesel variant, offering a balance of performance and economy.

Production Years Model:

1984-1995 (W124 platform). Specific 300D 2.5 Turbo variants likely from 1986 onwards, with the 1990-1993 range covered by this manual.

🏆 Awards & Recognition

Vehicle Reputation:

The W124 E-Class is widely regarded as one of the most over-engineered and durable Mercedes-Benz models ever produced, earning it a reputation for longevity and reliability when properly maintained.