🏷️ Basic Information Identification Make: Mercedes-Benz Model: 300D 2.5 Turbo Chassis Code: W124 (E-Class) Production Years Covered: 1990, 1991, 1992, 1993 Codes Engine Code: OM602.912 👋 Introduction Market Position Segment: Mid-size Luxury Sedan/Coupe/Convertible/Wagon Competitive Analysis Competitors: BMW 5 Series (E34), Audi 100/A6 (C3/C4), Volvo 240/740/940 Key Features Durability: Renowned for Mercedes-Benz's legendary build quality and long-term durability. Diesel Performance: The 2.5L turbo-diesel offered a compelling blend of torque, fuel economy, and respectable performance for its time. Comfort And Refinement: Exceptional ride comfort, quiet cabin, and premium interior appointments characteristic of the W124 chassis. 📋 Manual Details Coverage Areas Coverage Scope: Comprehensive Workshop Repair & Service Page Count Estimated Page Count: Over 800 pages (typical for this era's comprehensive manuals) Manual Type Manual Type: Workshop Repair Service Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Powertrain: Engine, Fuel System, Cooling System, Exhaust System, Transmission (Automatic & Manual), Drivetrain, Clutch Chassis: Suspension (Front & Rear), Steering, Brakes (Hydraulic & Parking), Wheels & Tires Electrical: Engine Control Unit (ECU), Ignition System, Lighting, Instrumentation, Power Accessories, Audio System, Battery, Charging System, Starting System Body: Body Panels, Doors, Windows, Seats, Interior Trim, Exterior Trim, HVAC System, Sunroof Procedures Included Maintenance: Scheduled Maintenance, Oil Change, Filter Replacement, Fluid Checks and Replenishment, Belt Replacement, Spark Plug Replacement (where applicable) Diagnostics: Troubleshooting Guides, Symptom-Based Diagnosis, Diagnostic Trouble Codes (DTCs), Electrical Schematics for diagnosis Repair: Component Removal and Installation, Engine Overhaul, Transmission Rebuild, Brake System Service, Suspension Component Replacement, Electrical Component Repair Specifications: Torque Values, Clearances, Timing Procedures, Fluid Capacities, Component Dimensions Technical Depth Depth: Detailed, professional level covering complete overhaul and advanced diagnostics. 📊 Manual Specifications File Format PDF Quality: High-resolution, text-searchable PDF for easy navigation and printing. Print Quality Printable Pages: Designed for clear printing of individual pages or sections. Binding Type Binding Recommendation: Digital format, recommended for viewing on computer, tablet, or printing for workshop use. Paper Type Recommended Print Paper: Standard printer paper is suitable for printed copies. ⚙️ Engine Specifications Primary Engine Engine Type: Inline-5 Cylinder, Turbocharged Diesel Displacement: 2.5 Liters (2497 cc) Performance Horsepower: Approx. 126 hp @ 4,000 rpm Torque: Approx. 201 lb-ft (273 Nm) @ 2,400 rpm Fuel System Injection System: Bosch VE Rotary Injection Pump with Turbocharger and Intercooler Fuel Type: Diesel Fuel Maintenance Glow Plugs: Crucial for cold starts; detailed replacement procedure included in manual. Technical Details Compression Ratio: 19.0:1 (typical) Bore X Stroke: 87.0 mm x 84.0 mm (typical) 🔧 Transmission Standard Transmission Type: 4-Speed Automatic (722.4) standard on most models, 5-Speed Manual (G50) available Optional Optional Transmission: 5-Speed Manual Transmission Features Automatic Features: Selectable modes (e.g., Economy/Sport) in some variants, torque converter lock-up. Fluid Specifications Automatic Transmission Fluid: MB Spec 236.2, 236.6, or 236.7 (refer to manual for specific year/model) Manual Transmission Fluid: MB Spec 235.0 (e.g., SAE 80W-90 gear oil, refer to manual) 📐 Dimensions Exterior Body Styles: Sedan (W124.030), Coupe (C124.030), Convertible (A124.030), Wagon (S124.030) Wheelbase: Approx. 2800 mm (Sedan) Weights Curb Weight: Approx. 3,300 - 3,600 lbs (1500 - 1630 kg), varies by body style and equipment 🛡️ Safety Features Ratings Crash Safety Era: Designed to meet safety standards of the late 1980s/early 1990s. Active Features Brakes: Front: Ventilated Discs, Rear: Solid Discs. ABS (Anti-lock Braking System) standard. Traction Control: Optional ASR (Acceleration Slip Regulation) available on some models. Passive Features Airbags: Driver's side airbag standard from 1991/1992 onwards (check specific VIN). Body Structure: Reinforced safety cell, crumple zones, side-impact protection beams. 💡 Technology Features Infotainment Audio System: Factory premium audio system, often with cassette player. Manual covers basic diagnostics and speaker replacement. Driver Assistance Cruise Control: Standard cruise control system, details on operation and troubleshooting included. Connectivity Power Accessories: Power windows, power mirrors, central locking. Manual covers electrical diagrams and repair for these systems. Hvac Climate Control: Automatic climate control (ACC) or manual HVAC system. Manual provides service and repair for blower motor, control modules, actuators, and refrigerant system. 🔧 Maintenance Service Intervals Oil Change Interval: Every 3,000 - 5,000 miles or annually (diesel specific, refer to manual for exact intervals and oil type). Fuel Filter Interval: Recommended every 15,000 - 30,000 miles (crucial for diesel systems). Air Filter Interval: Check every 15,000 miles, replace as needed (typically 30,000 miles). Transmission Fluid Interval: Recommended every 30,000 - 50,000 miles for automatic transmissions. Fluid Specifications Engine Oil Capacity: Approx. 7.5 Liters (7.9 US Quarts) with filter change. Recommended oil: MB Spec 229.1 or 229.5 (API CD/CF or higher diesel specification for this era, consult manual). Coolant Capacity: Approx. 9.5 Liters (10 US Quarts). Recommended coolant: MB Spec 325.0 (Glysantin G05 or equivalent). Brake Fluid Type: DOT 4 Known Issues Diesel Specific Concerns: Glow plug issues, injector problems, turbocharger wear, vacuum line degradation, exhaust manifold cracks, diesel fuel gelling in extreme cold. General W124 Concerns: Headlight switch failures, evaporator core...