🏷️ Basic Information

Make:

Mercedes-Benz

Model:

300TE (W124 Wagon)

Product Name:

Mercedes Benz 124 WAGON 300TE 3.0L 1987-1992 Service Repair Manual

Chassis Code:

W124 (S124 for wagon variant)

Engine Code:

M103.983 (typically)

👋 Introduction

Vehicle Segment:

Luxury Mid-size Station Wagon

Target Audience:

Owners and independent repair shops seeking detailed technical information for maintenance and repair of the W124 wagon.

Competitors:

BMW 5 Series Touring (E34), Audi 100/200 Avant (C3), Volvo 740/940 Estate, Saab 9000 CS/CD Wagon.

Vehicle Appeal:

Renowned for Mercedes-Benz build quality, durability, refined ride, and practicality of the wagon body style.

Manual Benefit:

Enables owners to perform a wide range of maintenance and repair tasks, saving money and ensuring proper upkeep of a classic vehicle.

📋 Manual Details

Covered Years:

1987, 1988, 1989, 1990, 1991, 1992

Covered Models:

300TE Wagon

Covered Engines:

3.0L Inline-6 (M103)

Estimated Page Count:

Approximately 700-900 pages (typical for comprehensive service manuals of this era, exact count not provided in product description)

Type:

Service and Repair Manual

Language:

English

Format:

Digital PDF (Instant Download)

📖 Manual Coverage

Engine:

Engine mechanicals, cylinder head, block, pistons, crankshaft, camshafts, timing system, lubrication, cooling system, fuel injection (Bosch KE-Jetronic), ignition system, emissions control.

Transmission:

4-speed Automatic Transmission (722.4 series): disassembly, assembly, adjustments, troubleshooting, fluid specifications.

Drivetrain:

Driveshafts, differentials, rear axle, wheel bearings.

Brakes:

Front and rear disc brakes, hydraulic system, parking brake, ABS (Anti-lock Braking System) troubleshooting and components.

Suspension:

Front and rear suspension systems, shock absorbers, springs, control arms, bushings, self-leveling rear suspension (if equipped).

Steering:

Power steering system, steering gearbox, steering column, linkage.

Electrical:

12V electrical system, battery, charging system (alternator), starting system (starter), lighting, gauges, switches, fuses, relays, wiring diagrams, body control modules, fuel pump relay, ABS control module.

Body:

Body panels, doors, hood, tailgate, interior trim, seats, glass, sunroof (if equipped), convertible top (if applicable to variant, though this is a wagon), rust prevention, body repair guidelines.

HVAC:

Heating, ventilation, and air conditioning (HVAC) system, compressor, refrigerant, blower motor, climate control panel, troubleshooting.

Maintenance:

Oil changes, filter replacements (oil, fuel, air), spark plug replacement, coolant flush, belt inspection/replacement, brake fluid flush, power steering fluid flush, transmission fluid service, chassis lubrication, differential fluid change.

Troubleshooting:

Diagnostic procedures for common problems, symptom-based troubleshooting guides for engine performance, electrical faults, braking issues, HVAC malfunctions.

Repair:

Engine component replacement (e.g., water pump, thermostat, alternator, starter, fuel injectors), transmission component replacement, brake caliper/rotor replacement, suspension component replacement, exhaust system repair, electrical component diagnosis and replacement.

Rebuild:

Detailed procedures for engine and transmission overhaul, including specifications for machining and assembly.

Diagnostics:

On-board diagnostics (OBD) information relevant to the era, troubleshooting flowcharts, electrical schematic interpretation.

Depth:

Comprehensive. Covers routine maintenance, diagnostics, repairs, and full component overhauls. Suitable for both DIY enthusiasts and professional mechanics.

Diagnostics Focus:

Detailed diagnostic procedures for fuel injection (KE-Jetronic), ignition, ABS, and electrical systems.

Schematics:

Includes detailed electrical wiring diagrams for all major systems.

📊 Manual Specifications

Format:

PDF

Searchability:

Likely searchable text (depending on original scan quality, but standard for professional PDFs).

Resolution:

High-resolution scan for clear text and diagrams.

Clarity:

Designed for readability and ease of use when printing pages.

Type:

N/A (Digital PDF)

Type:

N/A (Digital PDF)

⚙️ Engine Specifications

Engine Type:

Naturally Aspirated Inline-6 Cylinder

Displacement:

3.0 Liters (2962 cc)

Bore X Stroke:

88.5 mm x 80.25 mm (typical for M103)

Compression Ratio:

9.2:1 or 9.0:1 (depending on specific variant/market)

Horsepower:

Approximately 180-189 hp (SAE net) @ 5700-6000 rpm

Torque:

Approximately 184-188 lb-ft (SAE net) @ 4400-4500 rpm

Fuel Delivery:

Bosch KE-Jetronic (CIS-E) Electronic Fuel Injection

Fuel Type:

Unleaded Gasoline (Premium Octane recommended, typically 91 AKI or higher)

Ignition System:

Electronic Ignition with Distributor and Spark Control Unit (SCU).

🔧 Transmission

Type:

4-speed Automatic Transmission

Model Code:

722.4xx series (e.g., 722.405)

Type:

5-speed Manual Transmission (less common in US market for this model, but available).

Transmission Fluid:

MB 236.1 Specification (e.g., Mercedes-Benz Automatic Transmission Fluid or equivalent)

Fluid Capacity:

Approximately 5.5 - 6.5 Liters (11.6 - 13.8 US Quarts) for a fluid change with filter.

📐 Dimensions

Length:

4740 mm (186.6 in)

Width:

1740 mm (68.5 in)

Height:

1470 mm (57.9 in)

Wheelbase:

2800 mm (110.2 in)

Seating Capacity:

5-7 (with optional rear-facing third-row seat)

Cargo Volume:

Significant, with folding rear seats typical for a wagon.

Curb Weight:

Approximately 1500-1600 kg (3300-3530 lbs)

Gross Vehicle Weight Rating:

Varies, typically around 2100-2200 kg

🛡️ Safety Features

Crash Test Info:

No official NHTSA ratings from this era, but the W124 chassis was known for its robust safety cell and energy-absorbing crumple zones. Considered very safe for its time.

ABS:

Standard Anti-lock Braking System (ABS) from model year 1988 onwards.

Airbags:

Driver's side airbag became standard on many W124 models during this period, likely standard on later 300TEs. Passenger airbag was optional or not available on early models.

Seatbelts:

Height-adjustable front seatbelts, rear seatbelts.

Chassis Design:

Reinforced safety structure, side impact beams.

💡 Technology Features

Audio System:

Factory-installed AM/FM radio with cassette player. Often features premium sound system options with multiple speakers.

Antenna:

Power-operated automatic antenna.

Cruise Control:

Standard cruise control system.

ABS:

Standard Anti-lock Braking System (ABS) on most models within this range.

Oem Features:

No modern connectivity features like Bluetooth or USB. OEM communications systems (e.g., early car phones) were optional on higher trims.

🔧 Maintenance

Oil Change:

Every 7,500-10,000 miles (12,000-15,000 km) or annually, whichever comes first.

Air Filter:

Every 15,000-30,000 miles (24,000-48,000 km) or as needed based on conditions.

Fuel Filter:

Every 30,000 miles (48,000 km).

Spark Plugs:

Every 30,000 miles (48,000 km) for standard plugs; potentially longer for platinum or iridium plugs if specified.

Coolant Flush:

Every 2-3 years or 30,000-50,000 miles (48,000-80,000 km).

Engine Oil:

API SJ/SL or higher, SAE 10W-40 or 10W-30 (check owner's manual for specific ambient temperature ranges), Synthetic oils are often recommended for longevity.

Coolant:

MB 325.0 Specification (Ethylene Glycol based, green color) mixed 50/50 with distilled water.

Brake Fluid:

DOT 3 or DOT 4 (check manual for specifics), Mercedes-Benz recommends high-quality brake fluid.

Power Steering Fluid:

Pentosin CHF 11S or equivalent (check manual, often specific hydraulic fluid).

Engine M103:

Timing chain stretch (though less common than M104), oil leaks (e.g., oil cooler seals, valve cover gasket), injector seal leaks, distributor cap/rotor wear, MAF sensor issues (though KE-Jetronic uses a different airflow meter), vacuum leaks.

Transmission 722.4:

Leaking transmission cooler lines, worn modulator valve, electronic kickdown issues.

Electrical:

Wire harness degradation (especially under vacuum hoses), blower motor resistor failure, door lock actuator issues, self-leveling suspension issues (accumulator, pump, lines), ABS sensor failures.

Body Rust:

Common rust areas include wheel arches, rear fenders, jacking points, battery tray, and tailgate lower edges.

📚 Vehicle History

Brand Reputation:

Mercedes-Benz is synonymous with engineering excellence, luxury, and durability, with a long history dating back to the first automobile.

W124 Introduction:

The W124 chassis was introduced in 1984 as the successor to the W123. The wagon variant (S124) was launched in 1985.

300Te Introduction:

The 300TE, featuring the M103 3.0L engine, was introduced to offer more power and refinement within the W124 wagon lineup.

W124 Facelift:

The W124 received a significant facelift in 1989, with minor updates to styling (e.g., body-colored trim, updated grille, revised wheel options), interior, and some mechanicals. This manual covers pre and post-facelift models within its range.

Production Period:

1987-1992 (for this specific model variant)

Manufacturing Location:

Germany (primarily Sindelfingen and Bremen plants)

🏆 Awards & Recognition

Vehicle Awards:

While specific awards for the 1987-1992 300TE Wagon are not commonly cited, the W124 chassis as a whole received numerous accolades for its engineering, durability, and safety, often appearing on 'Best Cars' lists from automotive publications of the era.

Reliability:

The W124 generation is highly regarded for its long-term reliability and robust construction when properly maintained.