Positioning:
Essential DIY and professional workshop tool for owners and technicians of the 1990 Mercedes-Benz 300D
Value Proposition:
Provides official, factory-level technical data missing from generic online forums and basic repair guides
Official Licensing:
Officially licensed, ensuring accuracy and completeness of information
Digital Accessibility:
Instant online availability, searchable text, easily navigable digital format
Systems Covered:
Engine, Fuel System, Electrical System, Drivetrain, Suspension, Brakes, Steering, HVAC, Bodywork, Diagnostic Procedures, Maintenance Schedules
Page Count:
Extensive (Digital format implies comprehensive coverage, often exceeding 1000 pages in print equivalent)
Manual Type:
Service and Repair Manual Software
Format:
Software (Digital - likely PDF or proprietary application)
Engine Mechanical:
Detailed diagnostics, repair procedures, component overhaul for OM603.912 diesel engine
Fuel System:
Bosch inline injection pump servicing, glow plug system, fuel lines, filters
Electrical System:
Wiring diagrams, component testing, troubleshooting starter, alternator, lighting, and accessories
Drivetrain:
Automatic transmission (722.4) overhaul, service, and diagnostics; rear axle and driveshaft maintenance
Suspension And Steering:
Front and rear suspension component replacement, alignment procedures, power steering system repair
Brakes:
Disc brake system maintenance, ABS diagnostics and repair, brake fluid flush procedures
HVAC:
Air conditioning system service, heater core replacement, climate control unit troubleshooting
Body And Interior:
Door panel removal, glass replacement, seat adjustment, trim repair
Maintenance:
Oil change intervals, filter replacements, fluid checks and changes, belt inspection and replacement
Troubleshooting:
Step-by-step diagnostic flowcharts for common and uncommon issues, fault code interpretation
Repair:
Detailed, illustrated instructions for component removal, repair, and reinstallation
Diagnostics:
Wiring diagrams, component resistance values, pressure testing, vacuum testing procedures
Depth:
Comprehensive, covering routine maintenance to major overhauls and advanced diagnostics
Engine Type:
Inline 6-cylinder Diesel
Displacement:
2.996 cc (3.0 Liters)
Bore X Stroke:
87.0 mm x 84.0 mm
Compression Ratio:
22.0:1
Horsepower:
107 hp @ 4600 rpm (approx.)
Torque:
195 lb-ft @ 2400 rpm (approx.)
Injection Type:
Bosch M-Type Inline Fuel Injection Pump
Oil Type Recommendation:
API CD or higher, SAE 15W-40 or 10W-30 (depending on climate)
Oil Capacity:
7.5 Liters (with filter change)
Transmission Type:
4-Speed Automatic (722.4)
Optional Transmission:
5-Speed Manual (less common on 300D)
Automatic Features:
Lock-up torque converter, hydraulic control unit
Automatic Transmission Fluid:
MB 236.1 or 236.2 Specification ATF (e.g., Dexron II compatible)
Automatic Transmission Fluid Capacity:
Approx. 7.5 Liters (total capacity, varies with torque converter)
Safety Standards:
Built to meet stringent Mercedes-Benz safety standards of the era; specific crash test data may vary by region.
ABS:
Anti-lock Braking System (ABS) standard
Traction Control:
Optional ASR (Anti-Slip Regulation) available on some models
Airbags:
Driver's side airbag standard
Seatbelts:
Front and rear seatbelts with pretensioners
Radio System:
Factory AM/FM cassette radio with optional CD changer compatibility
Climate Control:
Manual or optional automatic climate control (Thermotronic)
Cruise Control:
Standard cruise control system
Phone Integration:
No integrated smartphone connectivity (features of the era were basic)
Oil Change Interval:
Typically every 5,000-7,500 miles or 12 months, whichever comes first, using appropriate diesel oil.
Fuel Filter Replacement:
Recommended every 20,000-30,000 miles
Air Filter Replacement:
Recommended every 15,000-20,000 miles
Transmission Service:
Fluid and filter change recommended every 30,000-50,000 miles
Coolant Type:
Mercedes-Benz Specification 325.0 (Ethylene Glycol based, typically 50/50 mix with distilled water)
Common Wear Items:
Glow plugs, vacuum lines, fuel injection pump seals, front suspension bushings, engine mounts, exhaust system corrosion.
Diesel Specific Issues:
Air in fuel system after filter changes, cold weather starting issues if glow plug system is faulty.
Mercedes Benz Legacy:
Mercedes-Benz has a long-standing reputation for engineering excellence, durability, and pioneering automotive technology since its inception.
W124 Era:
The 1990 300D is part of the highly regarded W124 E-Class generation, known for its robust construction and engineering precision.
300D Significance:
The 300D represented Mercedes-Benz's commitment to reliable, fuel-efficient, yet luxurious diesel sedans in the late 80s and early 90s.
Production Period:
W124 E-Class produced from 1984 to 1995. The 300D variant was a key model within this range.
