🏷️ Basic Information

Make:

Mercedes-Benz

Model:

300E 4MATIC

Body Style:

Sedan

Chassis Code:

W124

Model Years Covered:

1990-1993

Engine Variant:

3.0L Inline-6

Engine Code Common:

M103.980

Transmission Code Common:

722.4 (4-speed automatic)

👋 Introduction

Positioning:

The Mercedes-Benz W124 chassis represented the pinnacle of German engineering and build quality in its era, offering robust performance, exceptional durability, and sophisticated comfort, making it a highly sought-after luxury sedan and a future classic.

Competitors:

Competed directly with luxury sedans from BMW (E34 5-Series), Audi (V8 Quattro), and Lexus (LS 400), offering a blend of performance, comfort, and advanced engineering.

Design:

Aerodynamically efficient design, robust chassis construction, independent multi-link rear suspension, high-quality interior materials, advanced safety features for its time.

Powertrain:

Smooth and powerful M103 3.0L inline-six engine, coupled with the durable 4-speed automatic transmission and the advanced 4MATIC all-wheel-drive system for enhanced traction and stability.

Benefit To Owner:

Empowers owners to perform detailed maintenance, accurate diagnostics, and complex repairs, saving on dealership costs and preserving the longevity and value of their classic Mercedes-Benz.

📋 Manual Details

Scope:

Comprehensive service and repair

Estimated Pages:

Over 1500 (typical for comprehensive W124 service manuals)

Type:

Factory-authorized Service Manual / Workshop Repair Manual

Language:

English

Format:

Digital PDF (Instant Download)

📖 Manual Coverage

Engine:

All aspects including M103 engine diagnostics, tune-up, component testing, rebuild procedures, fuel injection (Bosch KE-Jetronic), ignition, emissions control.

Transmission:

4-speed automatic transmission (722.4) service, diagnostics, fluid changes, seal replacement, torque converter.

Drivetrain:

4MATIC all-wheel-drive system maintenance, troubleshooting, differential service, driveline components.

Suspension:

Front and rear suspension diagnostics, component replacement (struts, shocks, control arms, ball joints, bushings), alignment specifications.

Brakes:

Hydraulic braking system service, ABS (Anti-lock Braking System) diagnostics, rotor and pad replacement, brake fluid specifications, bleeding procedures.

Steering:

Power steering system service, component replacement, troubleshooting, steering column adjustments.

Electrical System:

Complete wiring diagrams, fuse and relay locations, starting and charging system diagnostics, battery service, lighting, horn, power accessories.

Body And Chassis:

Body panel repair, door and window mechanisms, interior trim removal, structural components, rust prevention.

HVAC:

Climate control system diagnostics, refrigerant service, blower motor, heater core, A/C compressor, cabin filter replacement.

Fuel System:

Fuel pump, fuel filter, fuel lines, fuel tank, fuel pressure regulator, injectors (KE-Jetronic).

Exhaust System:

Exhaust manifold, catalytic converter, muffler, O2 sensors (if applicable).

Maintenance:

Oil changes, filter replacements (oil, fuel, air, cabin), spark plug replacement, fluid level checks and top-offs, belt inspection and replacement.

Diagnostics:

System-specific troubleshooting guides, symptom-based diagnostics, fault code identification (OBD I era systems if applicable), component testing.

Repair:

Step-by-step instructions for component removal and installation, engine internal component repair, transmission overhaul, brake system overhauls, suspension component replacement.

Troubleshooting:

Detailed flowcharts and diagnostic trees for common and uncommon problems across all vehicle systems.

Specifications And Tolerances:

Torque specifications for all fasteners, engine clearance measurements, alignment angles, fluid capacities, electrical resistance values.

Wiring Diagrams:

Complete, high-resolution wiring diagrams for all electrical systems, including engine management, lights, accessories, and power windows.

Depth:

Expert level, covering everything from routine maintenance to complete engine and transmission overhauls, including advanced diagnostic procedures.

📊 Manual Specifications

Format:

Searchable PDF

Quality:

High-resolution scans, clear text and images

Searchability:

Full text searchable for quick information retrieval.

Printable:

Yes, optimized for home or professional printing.

Binding:

N/A (Digital)

Paper:

N/A (Digital)

Required Software:

Standard PDF reader (e.g., Adobe Acrobat Reader)

⚙️ Engine Specifications

Engine Type:

Naturally Aspirated Inline-6 Cylinder

Displacement:

2960 cc (3.0 Liters)

Bore X Stroke:

88.5 mm x 80.25 mm

Compression Ratio:

9.2:1

Horsepower:

Approx. 189 hp @ 5700 rpm

Torque:

Approx. 204 lb-ft @ 4400 rpm

Fuel Delivery:

Bosch KE-Jetronic Electronic Fuel Injection

Fuel Type:

Unleaded Premium Gasoline (91+ Octane Recommended)

Oil Capacity:

Approx. 8.0 liters (with filter)

Recommended Oil Viscosity:

SAE 10W-30 or 10W-40 (depending on climate)

🔧 Transmission

Type:

4-speed Automatic (722.4)

Drivetrain:

4MATIC All-Wheel Drive

Modes:

Comfort and Sport modes

Transmission Fluid:

MB-Approval 236.6 (e.g., Mobil ATF 220, Pentosin ATF 1)

Capacity:

Approx. 8.0 liters (total, including torque converter)

📐 Dimensions

Length:

4740 mm (186.6 in)

Width:

1740 mm (68.5 in)

Height:

1430 mm (56.3 in)

Wheelbase:

2795 mm (110.0 in)

Curb Weight:

Approx. 1660 kg (3660 lbs) - Varies with options

Gross Vehicle Weight Rating:

Approx. 2110 kg (4650 lbs)

Standard Wheel Size:

15-inch alloy

Standard Tire Size:

205/65R15

Bolt Pattern:

5x112

Center Bore:

66.5 mm

🛡️ Safety Features

Era Specific Safety:

Designed with advanced safety features for its time, including a robust crumple zone structure, reinforced safety cell, and energy-absorbing materials.

Airbags:

Driver's side airbag standard from 1991 model year onward; optional on earlier models.

Seatbelts:

Pre-tensioning front seatbelts, three-point rear seatbelts.

Anti Theft:

Factory immobilizer system (e.g., K-Alarm).

Brakes:

Four-wheel Anti-lock Braking System (ABS) standard.

Traction Control:

ASR (Acceleration Slip Regulation) was optional on some models, particularly later W124s, but less common on the 300E 4MATIC of this specific range.

Lighting:

Halogen headlamps, integrated fog lamps (often optional).

💡 Technology Features

Audio System:

Factory premium audio systems, often with cassette player and AM/FM radio. Later models may feature optional CD changers.

Cruise Control:

Standard cruise control system.

Climate Control:

Optional automatic climate control (Thermotronic) or manual climate control (Behr system) depending on specification.

Windows And Mirrors:

Power windows, power adjustable mirrors, optional heated mirrors.

Seats:

Power adjustable front seats with memory function (optional), heated front seats (optional).

🔧 Maintenance

Oil Change Interval:

Every 7,500 - 10,000 miles or annually, whichever comes first (depending on oil quality and driving conditions).

Transmission Fluid Service:

Every 30,000 - 50,000 miles or every 3-4 years. It's crucial to use the correct MB-approved fluid.

Air Filter Replacement:

Every 15,000 - 30,000 miles or annually.

Fuel Filter Replacement:

Every 30,000 miles. Essential for KE-Jetronic system health.

Spark Plug Replacement:

Every 30,000 miles (Bosch W8AC or equivalent).

Coolant Flush:

Every 2-3 years or 30,000 miles.

Engine Oil:

API SJ/SL or equivalent, 10W-30 or 10W-40.

Coolant:

Mercedes-Benz approved O.E. coolant (Glysantin G48 or equivalent) mixed 50/50 with distilled water.

Brake Fluid:

DOT 4.

Wiring Harness:

Cracked insulation on the engine wiring harness (biodegradable insulation common in this era) is a prevalent issue, leading to misfires and electrical gremlins. The manual will detail inspection and replacement procedures.

Head Gasket:

While generally robust, head gasket leaks can occur, particularly if the engine has been overheated. Diagnosis and replacement are covered.

Suspension Bushings:

Rubber suspension bushings (e.g., control arm bushings, sway bar bushings) can degrade over time, leading to clunking noises and vague handling. The manual provides replacement guides.

Fuel Accumulator:

The fuel accumulator in the KE-Jetronic system can fail, leading to hard starting when hot. The manual covers its testing and replacement.

Evaporative Emissions Control:

Canister purge valve or vacuum lines can leak, affecting idle and emissions. Manual will cover diagnosis.

Oil Filter Oem Example:

Mercedes-Benz: 103 180 02 09 (or equivalent Mann-Filter, Mahle)

Air Filter Oem Example:

Mercedes-Benz: 103 094 07 04 (or equivalent)

Fuel Filter Oem Example:

Mercedes-Benz: 001 477 03 02 (or equivalent)

Spark Plug Oem Example:

Bosch: W8AC (or equivalent)

📚 Vehicle History

Heritage:

Mercedes-Benz has a long-standing reputation for building durable, safe, and technologically advanced automobiles, with the W124 generation continuing this legacy by being over-engineered for longevity and reliability.

W124 Lineage:

The W124 (1984-1995) was the successor to the W123 and introduced significant advancements in aerodynamics, safety, and suspension design. The 300E 4MATIC variant specifically introduced all-wheel drive to the sedan lineup, enhancing its all-weather capability.

Production Period:

The W124 range was produced from 1984 to 1997 globally, with the 300E 4MATIC variants fitting within the later years of this lifecycle.

Manufacturing Location:

Primary production in Sindelfingen, Germany, with some assembly in other international locations.

Collectible Status:

Highly collectible due to its build quality, timeless design, and performance. Well-maintained examples are increasingly valued by enthusiasts.

🏆 Awards & Recognition

Reputation For Quality:

Consistently ranked among the most reliable and well-built cars of the 1980s and 1990s by automotive journalists and consumer surveys.

Industry Recognition:

The W124 platform was lauded for its engineering excellence and durability, often cited as a benchmark for luxury sedans. While specific awards for the 300E 4MATIC model might be scarce, the overall chassis received widespread critical acclaim.