Market Segment:
Luxury Executive Sedan with All-Wheel Drive capability, a segment Mercedes-Benz consistently dominated.
Key Competitors:
BMW 5 Series (e.g., 535i xDrive), Audi 100/A6 Quattro, Volvo 740/940 with AWD options.
4Matic System:
Mercedes-Benz's permanent all-wheel-drive system, enhancing traction and stability, particularly in adverse weather conditions.
W124 Chassis Reputation:
Renowned for exceptional build quality, durability, and ride comfort, often considered one of the most over-engineered cars of its era.
Manual Primary Objective:
To equip owners and technicians with the knowledge to accurately diagnose and repair the Mercedes-Benz 300E 4MATIC, ensuring optimal performance and longevity.
Engine Systems:
Engine oil and filter, valve clearance adjustment, idle speed control, fuel injection timing, fuel filter replacement, air filter replacement, V-belts, manifold seating, oxygen sensor replacement, spark plugs, cooling system, engine mounts.
Drivetrain Systems:
Clutch system (inspection, fluid), manual transmission (oil change, level check), automatic transmission (fluid/filter change, level check), transfer case (fluid change, level check), front axle oil, rear axle oil, drive shaft flexible coupling.
Suspension Steering Brakes:
Suspension and body structure inspection, level control (ADS, ASD, 4MATIC fluid), self-leveling suspension, ball joint inspection (front/rear axles), wheel inspection and rotation, tire pressure, wheel bolt tightening, brake fluid level, brake lines, brake pads and disc thickness, brake fluid replacement, parking brake adjustment, power steering fluid, steering play, steering bolt tightening.
Electrical Components:
Warning and indicator lamps, battery fluid level, headlamp and exterior lamp inspection, windshield wiper and washer inspection.
Body Chassis Comfort Systems:
Water leakage and corrosion inspection, throttle linkage lubrication, exhaust system connections, lower engine compartment panel removal/installation, door hinge/lock lubrication, hydraulic top fluid, sunroof rails, soft top locking tabs, windshield washer fluid, dust filter, active charcoal filter, recirculating air filter, folding side mirror lubrication, hood lubrication, safety belts, backrest lock, noise encapsulation panels, body paint damage inspection.
Maintenance Procedures:
Routine maintenance tasks such as fluid changes (engine oil, transmission, transfer case, power steering, clutch), filter replacements (oil, fuel, air), spark plug replacement, belt inspection, tire pressure checks, brake pad/disc inspection.
Diagnostic Procedures:
Troubleshooting vehicle problems, inspecting component conditions, checking fluid levels, diagnosing suspension and steering issues, identifying water leaks and corrosion.
Repair Rebuild Procedures:
Detailed procedures for disassembly, inspection of parts for reuse, rebuilding, and assembly of various components.
Depth Of Coverage:
Comprehensive coverage suitable for professional mechanics and experienced DIY enthusiasts, covering everything from basic fluid services to detailed component repair and adjustment.
Engine Configuration:
3.0 Liter (2962 cc) Inline 6-Cylinder, SOHC
Estimated Horsepower:
Approx. 177-188 hp (depending on specific market and tuning)
Estimated Torque:
Approx. 184-192 lb-ft (depending on specific market and tuning)
Fuel Injection System:
Bosch KE-Jetronic or EIS (Electronic Ignition System) with fuel injection.
Spark Plug Type:
Typically Bosch or equivalent, specific part number would be in manual (e.g., Bosch W8AC or W8AP).
Engine Oil Capacity:
Approx. 5.5 - 6.0 Liters (check manual for exact spec).
Engine Oil Specification:
MB 229.1 or API SG, SAE 10W-40 or 15W-40 (check manual for precise recommendation based on climate).
Oil Filter Part Number:
Typical Mann Filter: WH 845/1, Mahle: OC 103 (verify with specific vehicle VIN).
Transmission Type:
4-Speed Automatic Transmission (e.g., 4G-TRONIC, 722.3 or 722.4 series).
Optional Transmission Type:
Rarely, a 5-speed manual might have been available in some markets, but the 4MATIC variant was predominantly automatic.
Automatic Transmission Features:
Lock-up torque converter for improved fuel efficiency at higher speeds, electronic control for shift points.
Automatic Transmission Fluid Capacity:
Approx. 7.5 - 8.5 Liters (for complete fill, pan drop is less).
Automatic Transmission Fluid Specification:
MB 236.1 (e.g., Mobil ATF 220, Castrol TQ-D).
Automatic Transmission Filter Part Number:
Typical Mann Filter: H 126, Mahle: OX 104 (verify with specific vehicle VIN).
Transfer Case Fluid Capacity:
Approx. 1.0 - 1.2 Liters (check manual).
Transfer Case Fluid Specification:
MB 235.1 (e.g., GL-4 SAE 75W-90 or 80W-90 gear oil).
Historical Safety Reputation:
The W124 platform was designed with a strong emphasis on safety, featuring robust construction and crumple zones.
Active Safety Systems:
Anti-lock Braking System (ABS), optional Acceleration Skid Control (ASR) on some later models, 4MATIC all-wheel drive for improved traction.
Passive Safety Features:
Reinforced chassis, side-impact protection, driver and passenger airbags (standard on later models or optional), pretensioner seatbelts.
Infotainment System:
Typically a premium Becker or Blaupunkt sound system with AM/FM radio and cassette player. Some models may have integrated CD changers. Antenna mast is manually operated or power-assisted.
Driver Assistance Features:
ABS, optional ASR, 4MATIC all-wheel drive. Level control systems (ADS) and automatic locking differential (ASD) were also available on some variants, enhancing stability and traction.
Connectivity Features:
Limited by era, typically no integrated Bluetooth or navigation systems. Auxiliary input for external devices might be present on some aftermarket or later upgrades.
Engine Oil Service Interval:
Typically 10,000 - 15,000 km (6,000 - 9,000 miles) or 12 months, depending on driving conditions. Refer to manual for specific 'Service A' or 'Service B' intervals.
Transmission Fluid Service Interval:
Automatic Transmission: Every 60,000 - 80,000 km (40,000 - 50,000 miles) is a common recommendation, though some sources suggest longer intervals. Manual recommends checking condition. Manual Transmission: Check manual for specific interval, typically longer than automatic.
Brake Fluid Replacement Interval:
Every 2 years regardless of mileage, as brake fluid absorbs moisture.
Coolant Specification:
Mercedes-Benz Approved Antifreeze/Coolant (e.g., G48, typically a blue-green color), mixed with distilled water at a 50:50 ratio.
Power Steering Fluid Specification:
MB 236.3 (e.g., Pentosin CHF 11S or equivalent hydraulic fluid).
Clutch Fluid Specification:
DOT 3 or DOT 4 brake fluid (shared with brake system).
Common W124 Issues:
Coolant leaks (especially head gasket and thermostat housing), wiring harness insulation degradation (chrysler/silicone type), SRS system faults, window regulator failures, differential seal leaks, and potential rust in certain areas (wheel wells, rocker panels). Fuel accumulator failure on some systems. Door lock actuator issues.
