🏷️ Basic Information

Make:

Mercedes-Benz

Model:

300 TD Turbo

Model Code:

W123 (specific chassis designation for TD variants)

Chassis Code:

W123 Series

Engine Code Family:

OM617

Engine Variant:

OM617.952 (Turbocharged Diesel)

👋 Introduction

Positioning:

The Mercedes-Benz 300 TD Turbo (W123) was positioned as a robust, reliable, and luxurious mid-size diesel automobile, renowned for its build quality and longevity. It appealed to discerning buyers seeking efficiency and durability.

Competitors:

Competed with other premium diesel sedans and estates from marques like BMW, Audi, and Volvo, as well as certain American luxury brands. Its key differentiator was its legendary diesel engine reliability and Mercedes-Benz's strong brand reputation.

Vehicle Highlights:

OM617.952 turbocharged five-cylinder diesel engine known for torque and durability, comfortable and well-appointed interior, solid build quality, often available in wagon (S123) body style offering practicality.

Value For Buyers:

Provides essential diagnostic and repair information for owners and independent mechanics, enabling effective maintenance and troubleshooting of these classic Mercedes-Benz vehicles, thus preserving their longevity and value.

📋 Manual Details

Applicable Years:

1981, 1982, 1983, 1984, 1985

Vehicle Types:

Sedan, Coupe, Estate/Wagon (confirm specific coverage for TD model)

Estimated Page Count:

Varies by specific year's manual, but typically comprehensive for a service manual, likely several hundred pages per year.

Type:

Service and Repair Manual

Language:

English

Format:

PDF / WINRAR

📖 Manual Coverage

Engine Mechanical:

Engine disassembly, inspection, rebuilding, and assembly of all internal components, including pistons, rings, rods, crankshaft, camshaft, cylinder head, valves, and timing components.

Engine Fuel System:

Fuel injection system diagnostics and repair, including injection pump, injectors, fuel lines, fuel filters (primary and secondary), and associated sensors.

Engine Cooling System:

Cooling system inspection, coolant replacement, radiator, water pump, thermostat, hoses, and heater core servicing.

Engine Lubrication System:

Engine oil and filter change procedures, oil pump inspection, and oil pan servicing.

Engine Electrical System:

Glow plug system, starting system, charging system (alternator), battery maintenance, and basic ignition troubleshooting (for auxiliary systems if present).

Transmission Manual:

Manual transmission fluid change, checking and correcting fluid level, clutch system inspection and fluid servicing.

Transmission Automatic:

Automatic transmission fluid and filter change, checking and correcting fluid level.

Drivetrain:

Drive shaft flexible coupling inspection, front and rear axle oil level checks and changes, rear axle mount adjustments.

Suspension:

Suspension inspection, ball joint checks (with special tool mention), self-leveling suspension inspection and fluid level checks (for models equipped).

Steering:

Power steering fluid level checks, steering play assessment, and steering bolt retightening.

Brakes:

Brake fluid level checks, brake line inspection, brake pad and disc thickness checks, brake fluid replacement, parking brake adjustment and testing.

Body And Chassis:

Body structure inspection, water leakage and corrosion inspection, suspension and body structure inspection, lower noise encapsulation panel removal/installation, door hinge/lock lubrication, hood lubrication, sunroof maintenance, soft top checks.

Climate Control:

Heating and ventilation system diagnostics, dust filter replacement, active charcoal filter replacement, recirculating air filter replacement, AC refrigerant charge checks.

Electrical Accessories:

Warning and indicator lamp checks, windshield wiper/washer inspection and blade replacement, headlamp and exterior lamp inspection, windshield washer fluid level checks, antenna mast cleaning, cassette deck tone head cleaning.

Routine Maintenance:

Engine oil and filter change, fuel filter replacement, air filter cleaning/replacement, V-belt and poly V-belt checks, spark plug checks/replacement, coolant level/antifreeze checks, windshield washer fluid checks.

Engine Tuning:

Valve clearance adjustment and checking, idle speed adjustment and checking, injection timing checks and adjustments.

Transmission Maintenance:

Manual transmission oil change and level correction, automatic transmission fluid and filter change and level correction, transfer case fluid change and level correction.

Brake Maintenance:

Brake fluid replacement, parking brake adjustment and testing, brake pad/disc inspections.

Suspension And Steering Maintenance:

Ball joint inspection, steering system checks, wheel bolt tightening, tire pressure correction.

Troubleshooting:

Diagnosis of vehicle-related problems, component inspection for issues, identification of causes for problems.

Component Rebuilding:

Disassembly, inspection of parts for reuse, and rebuilding of components.

Depth:

Comprehensive. Covers basic maintenance to major component overhauls and diagnostics for the specified model years.

📊 Manual Specifications

Digital Format:

PDF / WINRAR

Compatibility:

Win95/98/ME/XP/vista/7/8/Linux/MAC, iOS/Android devices

Delivery Method:

Instant Download

Printability:

Printable from digital format, allowing for physical copy creation.

Binding Type Physical:

Not applicable for digital format, but a printed version would typically be a perfect-bound or spiral-bound manual.

Paper Type Physical:

Not applicable for digital format, but original manuals used durable paper suitable for workshop environments.

⚙️ Engine Specifications

Engine Type:

Inline 5-cylinder, turbocharged diesel

Engine Code:

OM617.952

Displacement:

3.0 Liters (2998 cc)

Horsepower:

Approximately 125 hp (varies slightly by specific year and market) at 4350 rpm

Torque:

Approximately 230 Nm (169 lb-ft) (varies slightly by specific year and market) at 2400 rpm

Fuel Injection Type:

Bosch inline mechanical fuel injection pump with indirect injection

Fuel Type:

Diesel

Coolant Capacity:

Approx. 9.5 Liters (10 US quarts)

Oil Capacity With Filter:

Approx. 7.5 Liters (8 US quarts)

Recommended Oil Viscosity:

SAE 15W-40 or 20W-50 diesel engine oil (check manual for specific MB approval)

🔧 Transmission

Transmission Type:

Often equipped with a 4-speed automatic transmission. A 4-speed manual transmission was also available.

Transmission Options:

4-speed Manual Transmission

Automatic Transmission Fluid Type:

MB Specification 236.1 or 236.2 Automatic Transmission Fluid (e.g., Dexron II)

Manual Transmission Oil Type:

MB Specification 235.0 Gear Oil (e.g., SAE 80W-90)

📐 Dimensions

Wheelbase:

Approx. 2794 mm (110 inches) for Sedan and Coupe. Estate typically similar.

Curb Weight:

Approx. 1500-1600 kg (3300-3500 lbs), varies by body style and equipment.

Gross Vehicle Weight Rating:

Varies, typically around 2000-2100 kg.

🛡️ Safety Features

Crash Safety Era:

Designed to earlier safety standards. While robustly built, lacks modern advanced safety features. Focus on passive safety through strong chassis and crumple zones.

Active Safety Features:

Four-wheel disc brakes (front ventilated), power assisted steering.

Passive Safety Features:

Reinforced passenger cell, energy-absorbing steering column, seat belts (front likely 3-point, rear lap belts or 3-point depending on configuration).

💡 Technology Features

Infotainment Features:

Basic analog radio with AM/FM, cassette player. Often had an antenna mast that could be manually cleaned.

Driver Assistance Systems:

Limited by era. May include features like cruise control on some models. No modern electronic driver aids (ABS, ESP, traction control were not standard or available).

Connectivity Features:

No built-in connectivity features by modern standards. Primarily focused on mechanical and electrical systems.

🔧 Maintenance

Oil Change Interval:

Typically every 7,500 to 10,000 miles (12,000 to 16,000 km) or 12 months, whichever comes first. Check manual for exact intervals with specific oil types.

Fuel Filter Interval:

Recommended replacement every 20,000 to 30,000 miles (32,000 to 48,000 km) or annually, especially crucial for diesel engines.

Air Filter Interval:

Inspect every oil change, replace as needed, typically every 15,000 to 30,000 miles (24,000 to 48,000 km).

Coolant Change Interval:

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

Valve Adjustment Interval:

Typically at 30,000 to 60,000 mile intervals, or if ticking noise is present. Check manual for specific mileage.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid (check manual for specific MB approval)

Power Steering Fluid Type:

MB Specification 236.3 Power Steering Fluid (e.g., Pentosin CHF 11S or equivalent)

Common W123 Td Issues:

Vacuum leak issues (affecting central locking, HVAC flaps), potential for rust (especially around wheel arches, sills), injector pump timing drift, glow plug system issues, radiator/hose degradation, turbocharger wear over time.

📚 Vehicle History

Brand Legacy:

Mercedes-Benz has a long-standing reputation for engineering excellence, luxury, and durability, particularly in diesel engine technology.

W123 Generation:

The W123 series (1976-1985) succeeded the W114/W115 series and was a major success for Mercedes-Benz, known for its build quality and reliability. The 300 TD Turbo variant introduced turbocharged diesel power to the lineup, enhancing performance.

Production Years:

The W123 series was produced from 1976 to 1985. The 300 TD Turbo models specifically fall within the later years of this production run.

🏆 Awards & Recognition

Model Reputation:

The W123 series is widely regarded as one of Mercedes-Benz's most durable and reliable models, often cited in automotive journalism for its exceptional longevity and engineering. The 300 TD Turbo is a celebrated variant of this successful platform.