🏷️ Basic Information

Make:

Mercedes-Benz

Model:

S500

Model Code:

W140

Year:

1998

👋 Introduction

Market Position:

The 1998 Mercedes-Benz S500 (W140) represented the pinnacle of luxury and automotive engineering for its era. This manual caters to owners and technicians seeking to maintain and repair this high-end luxury sedan.

Competitive Analysis:

Competed directly with other flagship luxury sedans such as the BMW 7 Series, Audi A8, Lexus LS400, and Jaguar XJ. The W140 was known for its robust construction, advanced technology, and unparalleled comfort.

Key Features:

The S500 was powered by a potent V8 engine, featured advanced electronic systems for its time, and offered a supremely comfortable and quiet cabin. This manual is essential for understanding and servicing these complex systems.

📋 Manual Details

Coverage Areas:

Complete Service, Repair, Diagnostics, Maintenance, Electrical Schematics, Bodywork, Troubleshooting, Specifications

Page Count:

Estimated 1000+ pages (typical for comprehensive factory service manuals)

Manual Type:

Factory Authorized Service & Repair Manual Software

Language:

English

Format:

Digital Software (likely PDF or proprietary viewer)

📖 Manual Coverage

Engine Mechanical:

Engine assembly, cylinder head, valve train, piston rings, crankshaft, camshafts, timing system, oil pump, oil cooler, lubrication system.

Engine Management:

Fuel injection system (Bosch ME 2.0), ignition system, electronic engine control unit (ECU), sensor diagnostics, emission controls, idle speed control, OBD-II diagnostics.

Transmission:

5-speed automatic transmission (722.6 '5G-TRONIC'), transmission control unit (TCU), hydraulic system, gear shift mechanisms, fluid specifications, filter replacement, torque converter.

Brakes:

Hydraulic brake system, Anti-lock Braking System (ABS) (e.g., Bosch 5.3 or similar), brake discs, brake pads, brake calipers, brake fluid specifications, bleeding procedures, parking brake.

Suspension:

Front suspension (double wishbone), rear suspension (multi-link independent), shock absorbers, springs, bushings, sway bars, self-leveling suspension (if equipped), hydraulic suspension components.

Steering:

Hydraulic power steering system, steering rack, power steering pump, steering column, alignment specifications.

Electrical System:

12V electrical system, battery, alternator, starter motor, wiring diagrams, fuses, relays, lighting systems (headlights, taillights, interior), power windows, power locks, power seats, sunroof operation.

Climate Control:

Automatic climate control (ACC), HVAC system, A/C compressor, refrigerant specifications, blower motor, temperature sensors, air distribution.

Body And Interior:

Body panel removal and installation, door mechanisms, hood and trunk latches, interior trim panels, upholstery, sound deadening, paint codes, rust prevention.

Safety Systems:

Airbag system (SRS), seat belt mechanisms, restraint system diagnostics, emergency trunk release.

Scheduled Maintenance:

Oil and filter changes, air filter replacement, fuel filter replacement, spark plug replacement, coolant flush and replacement, brake fluid flush, transmission fluid and filter service.

Diagnostic Procedures:

Troubleshooting guides for common symptoms, diagnostic trouble codes (DTCs) interpretation, wiring harness testing, sensor testing, component testing using specialized tools (e.g., STAR diagnosis).

Repair Procedures:

Step-by-step instructions for component removal, disassembly, inspection, repair, and reassembly of all major vehicle systems.

Electrical Diagnostics:

Detailed wiring diagrams with component identification, troubleshooting flowcharts for electrical faults, testing procedures for circuits and components.

Engine Rebuild:

Full engine disassembly and reassembly procedures, torque specifications for critical fasteners, cylinder bore honing, piston and ring installation, bearing clearance checks.

Transmission Overhaul:

Detailed steps for transmission removal, disassembly, inspection of clutches, seals, and hydraulic components, reassembly, and filling with correct fluid.

Brake System Service:

Brake pad and rotor replacement, caliper service, ABS component testing, brake line replacement, bleeding procedures.

Suspension Component Replacement:

Replacement of shock absorbers, control arms, ball joints, tie rods, and other suspension parts, including alignment specifications.

Body Panel Repair:

Instructions for removing and installing body panels, door hinges, trunk lid, and associated trim, as well as basic bodywork and dent repair.

Interior Component Service:

Removal and installation of dashboard components, door panels, seating, and other interior trim for access to underlying systems.

Technical Depth:

Comprehensive: Covers basic maintenance to advanced diagnostic and repair procedures, including detailed specifications and torque values for all components. Suitable for professional technicians and advanced DIY enthusiasts.

📊 Manual Specifications

File Format:

Likely CD-ROM or downloadable digital format, optimized for searchability and cross-referencing. Often includes interactive diagrams.

Print Quality:

N/A (Digital format; original print quality would be high-resolution factory publication)

Binding Type:

N/A (Digital format)

Paper Type:

N/A (Digital format)

⚙️ Engine Specifications

Engine Type:

V8 SOHC (Single Overhead Cam)

Engine Code:

M119.970

Displacement:

5.0 Liters (4973 cc)

Horsepower:

302 hp @ 5600 rpm (approx.)

Torque:

339 lb-ft @ 3900 rpm (approx.)

Fuel Injection:

Bosch Motronic M1.3 or ME 2.0 electronic fuel injection

Fuel Type:

Premium Unleaded Gasoline (91 Octane or higher)

Ignition System:

Distributorless ignition system (DIS) with coil packs.

Coolant Type:

MB 325.0 specification coolant (typically a green ethylene glycol-based coolant)

Oil Capacity With Filter:

8.0 Liters (8.5 US Quarts) - Check manual for exact specification

Recommended Oil Viscosity:

SAE 5W-40 or 0W-40 Synthetic (Refer to Owner's Manual or MB Service Bulletin for precise specification)

🔧 Transmission

Transmission Type:

5-speed Automatic (722.6 '5G-TRONIC')

Electronic Control:

Electronically controlled shifting with multiple modes (Comfort, Sport).

Torque Converter Lockup:

Yes, for improved fuel efficiency.

Transmission Fluid Type:

MB Specification 236.14 (or compatible ATF)

Transmission Fluid Capacity Dry:

Approx. 7.5 Liters (7.9 US Quarts) - Check manual for exact specification

📐 Dimensions

Length:

5163 mm (203.3 in)

Width:

1886 mm (74.3 in)

Height:

1487 mm (58.5 in)

Wheelbase:

3137 mm (123.5 in)

Curb Weight:

Approx. 1980 kg (4365 lbs)

🛡️ Safety Features

Crash Test Results:

While official NHTSA/IIHS ratings from this era are scarce, the W140 was designed with a very robust chassis and advanced safety features for its time, contributing to strong real-world crash performance.

Airbags:

Driver and front passenger airbags (SRS), potentially side airbags depending on options.

Seat Belts:

Front and rear seat belts with pre-tensioners.

Chassis Construction:

High-strength steel unibody construction for passenger safety.

ABS:

Standard Anti-lock Braking System (ABS).

Traction Control:

Standard Acceleration Skid Control (ASR) or Traction Control System (TCS).

💡 Technology Features

Infotainment System:

Early generation COMAND (Cockpit Management and Navigation) system, or simpler radio/cassette with CD changer option. Features may include: cassette player, AM/FM radio, optional CD changer, navigation system (early generation maps), and basic climate control interface.

Driver Assistance:

ABS, ASR (Acceleration Skid Control), Cruise Control, Parktronic (optional parking assist sensors).

Connectivity:

Limited by modern standards. Likely includes basic diagnostics port (OBD-II) and potentially early cellular phone integration (via cradle).

Comfort Features:

Dual-zone automatic climate control, heated and ventilated multi-contour front seats with memory, power adjustable steering column, power-operated rear sunshade, electrochromic rearview mirror, rain-sensing wipers (optional).

🔧 Maintenance

Oil Change Interval:

Typically every 7,500 - 10,000 miles or annually, using synthetic oil. Consult the manual for the 'Service A' or 'Service B' intervals.

Transmission Service Interval:

Every 40,000 - 60,000 miles for fluid and filter change. Check manual for specific recommendations.

Spark Plug Replacement Interval:

Typically every 60,000 - 100,000 miles for iridium or platinum plugs, depending on type. Refer to manual for exact interval.

Brake Fluid Flush Interval:

Every 2 years, regardless of mileage.

Power Steering Fluid:

MB Specification 236.3 hydraulic fluid (or equivalent)

Coolant Type:

MB 325.0 specification coolant (typically a green ethylene glycol-based coolant)

Known Issues:

Common issues on the W140 include: Headlight leveling system failure, coolant leaks from the 'octopus' connector or oil cooler seals, ABS/ASR warning lights due to wheel speed sensor or control module issues, sagging headliner, window regulator failures, catalytic converter failure (rare but costly), and SRS system faults.

Common Repairs:

Regular replacement of front and rear brake pads and rotors, suspension bushings, and front shock absorbers due to wear. Addressing minor coolant leaks promptly is crucial to prevent catastrophic engine damage.

📚 Vehicle History

Brand Heritage:

Mercedes-Benz has a long-standing reputation for producing luxurious, technologically advanced, and durable vehicles, with the S-Class line representing the flagship of their sedan offerings.

W140 Generation:

The W140, produced from 1991 to 1998, was a significant departure from its predecessor (W126), featuring a larger, more imposing design, and incorporating many then-revolutionary technologies like CAN bus communication, bi-Xenon headlights (optional), and dual-pane glazing.

Production Period:

1991-1998

Key Updates 1998:

The 1998 model year saw refinements to the engine management system and continued availability of advanced features. The 5G-TRONIC transmission became standard across the range.

🏆 Awards & Recognition

Recognitions:

While specific awards for the 1998 model are not widely publicized, the W140 generation as a whole was consistently praised for its luxury, build quality, and technological advancements by automotive journalists and critics upon its release, solidifying Mercedes-Benz's position in the ultra-luxury segment.