🏷️ Basic Information

Make:

Mercedes-Benz

Model:

S-Class

Chassis Code:

W140

Body Style Variant Code:

C140 (Coupe)

Model Year:

1992

👋 Introduction

Target Audience:

Mercedes-Benz S-Class W140/C140 owners, independent repair shops, automotive technicians.

Advantage:

Provides factory-specific, A-Z repair information directly comparable to dealership service documentation. Offers comprehensive coverage not found in generic repair guides.

Unique Selling Proposition:

Vehicle-specific, step-by-step instructions, detailed diagrams, wiring schematics, and specifications for complete vehicle repair and maintenance. Digital format offers convenience and print-on-demand capability.

Benefit To Owner:

Enables owners to perform maintenance and repairs themselves, saving on labor costs, or to better understand and communicate with professional mechanics.

📋 Manual Details

Primary Coverage:

1992 Mercedes-Benz S-Class W140 and C140 models

Engine Coverage:

All engine variants offered for the 1992 model year

Estimated Page Count:

Varies by specific models and engine configurations, typically extensive for factory service manuals.

Type:

Factory Service and Repair Manual

Language:

English

Format:

PDF (Digital)

📖 Manual Coverage

Powertrain:

Engine mechanical, fuel system, lubrication, cooling, ignition, starting, charging, emissions control, automatic transmission (likely including 722.3, 722.4, 722.6 variants depending on specific engine), manual transmission (less common for W140, but covered if applicable).

Chassis:

Suspension (front and rear), steering (power steering, steering column), brakes (hydraulic, ABS, parking brake), wheels and tires.

Electrical:

Complete electrical system, wiring schematics, lighting, instrumentation, multiplex/CAN communication (early stages of development for this era), battery, charging system, starting system.

Body And Interior:

Body panels, doors, locks, windows, glass, mirrors, instrument panel, seats, engine hood, exterior/interior trim, air conditioning system, supplemental restraint system (SRS/Airbag), seat belts.

Control Systems:

Engine control module (ECM), transmission control module (TCM), ABS control module, and potentially early forms of body control modules. Diagnostic procedures.

Maintenance:

Routine maintenance schedules, fluid changes, filter replacements, inspections, lubrication.

Diagnostics:

Troubleshooting guides, fault code interpretation (where applicable for the era), diagnostic testing procedures for all major systems.

Repair:

Step-by-step repair instructions for all components and systems, including major overhauls and component replacement.

Component Rebuild:

Detailed instructions for rebuilding engines, transmissions, and other major components.

Wiring Schematics:

Comprehensive, high-detail wiring diagrams for all vehicle systems.

Depth:

Factory-level detailed, covering everything from basic maintenance to complex diagnostic and repair procedures. Suitable for professional technicians and advanced DIY enthusiasts.

📊 Manual Specifications

File Format:

PDF

Printability:

All pages are printable at original quality.

Image Resolution:

High-resolution, allowing for zooming and enlargement of diagrams and illustrations.

Binding Type:

Not applicable (Digital PDF)

Paper Type:

Not applicable (Digital PDF)

Operating Systems:

Windows (Vista32/64, XP, ME, 98, NT, 2000) and Mac OS

Software Requirements:

Adobe PDF Reader and Winzip (or similar decompression utility)

⚙️ Engine Specifications

Engine Options 1992:

Typically included the M119 4.2L V8 (420SEL/SEC), M120 5.0L V8 (500SEL/SEC), and M119 5.0L V8 (500SEL/SEC), and M104 3.0L Inline-6 (300SE/SEL).

M119 5.0L V8 Approx Hp:

~322 hp

M119 5.0L V8 Approx Torque:

~354 lb-ft

M120 6.0L V12 Approx Hp:

~408 hp (introduced later in the W140 lifecycle, but relevant for the platform family)

Fuel Injection:

Bosch KE-Jetronic or later LH-Jetronic (depending on specific engine and emissions standards).

Coolant Type:

Mercedes-Benz specifications (e.g., MB 325.0 - Antifreeze/Coolant Concentrate, Glysantin G05 or equivalent).

Engine Oil Spec SAE:

Typically SAE 0W-40, 5W-40, or 10W-40 synthetic oil, depending on climate and specific engine (refer to manual for exact MB-Approval specifications).

Engine Oil Capacity V8:

Approximately 8 liters (8.5 US quarts) for V8 models (refer to manual for exact specification).

🔧 Transmission

Transmission Type Common:

4-speed automatic (722.3, 722.4) and later 5-speed automatic (722.6) transmissions.

Transmission Options:

Manual transmission was extremely rare or not offered on the W140/C140 in most markets for this year. Manual coverage is unlikely to be extensive.

Transmission Fluid Spec:

MB Specification 236.1, 236.3, or 236.10 (e.g., Mobil ATF 220, Dexron III equivalent for earlier units; 722.6 typically requires MB 236.10 or similar).

Automatic Transmission Fluid Capacity:

Approximately 3-4 liters for torque converter refill, up to 8-9 liters for a complete overhaul/flush (refer to manual).

📐 Dimensions

W140 Sedan Length Approx:

5163 mm (203.3 in)

W140 Sedan Width Approx:

1886 mm (74.3 in)

W140 Sedan Height Approx:

1487 mm (58.5 in)

C140 Coupe Length Approx:

4960 mm (195.3 in)

W140 Sedan Curb Weight Approx Kg:

1850 - 2000 kg (4079 - 4409 lbs)

C140 Coupe Curb Weight Approx Kg:

1950 - 2100 kg (4300 - 4630 lbs)

Wheelbase W140 Sedan Mm:

3140 mm (123.6 in)

Wheelbase C140 Coupe Mm:

2945 mm (116.0 in)

Standard Tire Size Examples:

215/60 R16, 225/55 R16, 235/60 R16 (depending on engine and trim)

Wheel Bolt Pattern:

5 x 112 mm

Center Bore Mm:

66.6 mm

🛡️ Safety Features

Safety Ratings Era:

NHTSA/IIHS ratings from this era are less standardized than modern ratings. Emphasis was on passive safety features and structural integrity.

Active Safety Systems:

Anti-lock Braking System (ABS) standard on all models, Traction Control System (ASR) available on some models.

Passive Safety Features:

Front airbags (driver and passenger), reinforced body structure, crumple zones, side-impact protection beams, pre-tensioned seat belts.

Supplemental Restraint System:

SRS (Airbag) system coverage included.

💡 Technology Features

Infotainment Systems 1992:

High-end analog radio/cassette systems, with optional CD changers. Early GPS systems were very rudimentary and not widespread.

Driver Assistance 1992:

ABS and ASR were the primary driver assistance systems. Cruise control was standard on most models.

Connectivity 1992:

Limited to analog telecommunications if an optional car phone was fitted. No digital integration as known today.

Climate Control System:

Advanced dual-zone automatic climate control (THERMATIC/THERMOTRONIC) with cabin air filtration and vacuum-actuated flap control.

🔧 Maintenance

Oil Change Interval Approx:

Typically every 7,500 to 10,000 miles (12,000 to 16,000 km) or annually, depending on usage and oil type used. Refer to manual for exact service indicator (ASSYST) parameters.

Transmission Fluid Change Interval Approx:

Every 50,000 to 60,000 miles (80,000 to 96,000 km) or as indicated by service indicators. Critical for longevity of these complex transmissions.

Spark Plug Replacement Interval:

Varies significantly by engine type (e.g., 30,000-50,000 miles for older plugs, up to 100,000 miles for iridium plugs if fitted later). Refer to manual for specific engine.

Power Steering Fluid Spec:

MB Specification 236.3 or 343.0 (Hydraulic Fluid, typically mineral oil based).

Brake Fluid Spec:

DOT 4 (MB Specification 331.0).

Common W140 Issues 1992:

Water pump seals, head gasket leaks (especially on M119 engines), biodegradable wiring insulation degradation (though more prevalent on later W140s), vacuum line leaks affecting climate control and central locking, transmission conductor plate issues (on 722.6), differential seals, ignition coil failures, sagging headliner.

Common C140 Issues 1992:

Similar to W140 sedan, with particular attention to the hydraulic system for convertible tops (if applicable to earlier models, though primarily a later feature), and the more complex electrical systems.

📚 Vehicle History

Brand Positioning:

Mercedes-Benz is renowned for luxury, engineering excellence, safety, and durability. The S-Class represents the pinnacle of their automotive offerings.

W140 Introduction:

Introduced in 1991 as a replacement for the W126 S-Class, the W140 was a significant technological leap, larger, heavier, and more feature-rich.

C140 Introduction:

The C140 Coupe (CL-Class from 1996 onwards) was introduced in 1992, sharing many components with the W140 sedan but featuring a distinct two-door body style.

W140 Platform Significance:

This generation pushed boundaries with features like dual-pane glass, heated windshield wipers, and advanced engine management. It was a statement of automotive luxury and engineering prowess for its time.

Production Years W140:

1991-1998

Production Years C140:

1992-1999

Manufacturing Location:

Germany (Sindelfingen plant)

🏆 Awards & Recognition

Historical Recognition:

The W140 S-Class was widely recognized for its engineering, comfort, and refinement, setting benchmarks in the luxury sedan segment. It was often praised for its vault-like cabin and smooth ride.