🏷️ Basic Information

Make:

Mercedes-Benz

Model:

G-Class

Chassis Code:

W463

Model Years Covered:

1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997

👋 Introduction

Vehicle Segment:

Luxury Off-Road SUV / All-Wheel Drive (AWD)

Target Audience:

Enthusiasts, owners performing DIY maintenance and repairs, independent workshops specializing in Mercedes-Benz.

Competitors Early 90S:

Land Rover Range Rover, Toyota Land Cruiser, Jeep Grand Cherokee (though G-Class occupied a unique, more utilitarian yet luxurious niche).

Vehicle Identity:

The W463 G-Class is renowned for its exceptional off-road capability, robust construction, distinctive boxy styling, and luxurious interior appointments, differentiating it from most contemporary SUVs.

Manual Value Proposition:

Empowers owners to maintain and repair their vehicle, saving significant costs associated with dealership services. Provides detailed, accurate information for complex tasks.

📋 Manual Details

General Coverage:

Complete workshop service and repair procedures for Mercedes-Benz W463 G-Class models from 1990-1997.

Engine Coverage:

All gasoline and diesel engine variants offered for the W463 chassis during the specified years.

Transmission Coverage:

All automatic and manual transmission types, including transfer case.

Trim And Options Coverage:

All trim levels, body styles, and optional equipment.

Estimated Pages:

Extensive (typical for comprehensive workshop manuals covering multiple years and configurations).

Type:

Workshop Service Repair Manual

Language:

English

Delivery Format:

Digital Downloadable (PDF)

📖 Manual Coverage

Powertrain:

Engine mechanicals, lubrication, cooling, fuel injection (including mechanical and electronic systems), ignition, exhaust, diesel injection, turbocharging.

Transmission Drivetrain:

Automatic transmission (e.g., 722.4, 722.6 variants), manual transmission, transfer case, driveshafts, differentials, axles.

Chassis Suspension Steering:

Front and rear suspension (coil springs, shocks, control arms), steering system (power steering), wheel alignment.

Brakes:

Hydraulic brake systems (ABS if equipped), disc and drum brake components, parking brake.

Electrical Electronic:

Battery, charging system, starting system, lighting system, instrumentation, wipers, horn, power accessories, basic diagnostic codes.

Body And Interior:

Body panels, doors, windows, seats, interior trim, HVAC system, fuel tank, exhaust system routing.

Routine Maintenance:

Oil changes, filter replacements, fluid checks and top-offs, belt inspections and tensioning, spark plug replacement, air filter replacement.

Engine Repair:

Engine overhaul, cylinder head removal/installation, piston and connecting rod service, crankshaft service, timing component replacement.

Transmission Repair:

Transmission removal/installation, internal component repair (where feasible in a manual), fluid and filter changes.

Brake Service:

Brake pad and rotor replacement, caliper service, brake fluid flush and bleeding, parking brake adjustment.

Electrical Diagnostics:

Troubleshooting electrical circuits, component testing, wiring diagram interpretation.

Suspension Steering Repair:

Replacement of ball joints, tie rod ends, shock absorbers, springs, power steering pump and rack service.

Troubleshooting:

Diagnostic charts and procedures for common symptoms and issues.

Body Repair:

Body panel alignment, door and window mechanisms, tailgate repair, bumper repair/replacement.

HVAC System:

Heater core replacement, blower motor service, AC system diagnostics and recharging (where applicable).

Wiring Diagrams:

Detailed wiring diagrams for various electrical systems, crucial for troubleshooting.

Depth:

Comprehensive; covers everything from basic maintenance and fluid changes to complete engine and transmission rebuilds, and detailed diagnostic procedures.

📊 Manual Specifications

Format:

PDF

Quality:

High Quality (as stated in product description), suitable for printing.

Binding:

Not Applicable (Digital Download)

Paper Type:

Not Applicable (Digital Download)

Required Software:

Adobe Reader (or compatible PDF viewer)

⚙️ Engine Specifications

Engine Code:

M103

Engine Type:

3.0L Inline-6 SOHC

Bore X Stroke:

88.5 mm x 80.2 mm

Compression Ratio:

9.2:1

Horsepower:

Approx. 170-180 hp @ 5700 rpm

Torque:

Approx. 180-188 lb-ft @ 4400 rpm

Engine Code:

M104

Engine Type:

3.2L Inline-6 DOHC (24-valve)

Bore X Stroke:

89.9 mm x 84.0 mm

Compression Ratio:

9.0:1 or 10.0:1 (depending on variant)

Horsepower:

Approx. 210-230 hp @ 5500-6000 rpm

Torque:

Approx. 221-236 lb-ft @ 3750-4500 rpm

Diesel Variants:

OM602 (2.9L I5 Diesel), OM603 (3.0L I6 Diesel), OM606 (3.0L I6 Turbo Diesel).

Fuel Delivery Gasoline:

Bosch KE-Jetronic (CIS-E) or HFM (Hot Film Mass Airflow) fuel injection system.

Fuel Delivery Diesel:

Mechanical or electronic diesel injection pump.

🔧 Transmission

Standard Type:

Often equipped with a 4-speed automatic transmission (e.g., 722.4).

Optional Type:

Later models and specific variants might have a 5-speed automatic (e.g., 722.6) or a 5-speed manual transmission.

Transfer Case:

Permanent all-wheel drive with a 2-speed transfer case and lockable center differential, rear differential, and front differential (often selectable).

📐 Dimensions

Length:

Approx. 4665 mm (183.7 in) for long wheelbase versions.

Length:

Approx. 4060 mm (159.8 in) for short wheelbase versions (less common in W463 for this era).

Width:

Approx. 1760 mm (69.3 in).

Height:

Approx. 1931 mm (76.0 in).

Curb Weight:

Approx. 4800-5500 lbs (2177-2495 kg), varies significantly by engine and equipment.

🛡️ Safety Features

Crash Test Standards:

While specific contemporary NHTSA/Euro NCAP ratings for this exact period are scarce, the G-Class was built to robust military-derived standards emphasizing structural integrity and occupant protection.

ABS:

Anti-lock Braking System (ABS) available as standard or optional depending on model year and trim.

Airbags:

Driver airbag standard, passenger airbag often optional or standard on later models within this range.

Body Construction:

Body-on-frame construction providing significant structural rigidity.

💡 Technology Features

Audio System:

Factory-provided AM/FM radio with cassette player, often with upgraded speaker systems. CD changers were an option.

Navigation:

Early GPS navigation systems were rare and highly optional, if available at all in this early W463 era.

Cruise Control:

Standard on most models.

Phone Integration:

Optional dealer-installed or aftermarket phone kits were available.

🔧 Maintenance

Oil Change Interval:

Typically every 7,500-10,000 miles (12,000-16,000 km) or 12 months, whichever comes first, depending on driving conditions.

Transmission Fluid Service:

Recommended every 30,000-50,000 miles (48,000-80,000 km) for automatic transmissions, though some sources suggest longer intervals or 'lifetime' fluid depending on the specific transmission.

Coolant Service:

Every 2-3 years or 30,000-60,000 miles, depending on coolant type.

Engine Oil:

API SJ or higher, SAE 5W-40 or 0W-40 is commonly recommended (refer to specific engine and climate). Check manual for exact MB-Approval specification.

Transmission Fluid Auto:

MB 236.3 or MB 236.1 for earlier 4-speed automatics, MB 236.10 or MB 236.14 for later 5-speed automatics. Always confirm with vehicle VIN.

Coolant:

Mercedes-Benz approved G48 or equivalent (blue/green ethylene glycol based).

Brake Fluid:

DOT 4 or DOT 3 (confirm specific requirement for ABS models).

Common Wear Items:

Ball joints, tie rod ends, wheel bearings, door hinges, and tailgate hinges can wear due to weight and usage. Older electrical connectors can be prone to corrosion.

Engine Specific:

M103/M104: Head gasket leaks, oil leaks from various seals, timing chain guides (especially on M104). Diesel engines: Glow plug issues, injector pump seals.

Transmission Specific:

Automatic transmission cooler lines can corrode and leak. Torque converter seals can fail.

Rust:

While robust, common rust areas can include wheel arches, door sills, and the tailgate, particularly in harsh climates. Frame rust is less common but possible on older, poorly maintained examples.

📚 Vehicle History

Mercedes Benz History:

Mercedes-Benz, a marque synonymous with engineering excellence, luxury, and pioneering automotive technology since the late 19th century.

G Class Development:

Originally developed in the 1970s for military applications, the G-Wagen transitioned into a civilian luxury off-roader, with the W463 representing a significant redesign for enhanced on-road comfort and luxury while retaining its core off-road prowess.

Manufacturing Location:

Graz, Austria (by Magna Steyr under contract for Mercedes-Benz).

🏆 Awards & Recognition

Off Road Capability:

Universally recognized for its superior off-road prowess, often outperforming purpose-built competitors. Frequently lauded by off-road publications and used by various governments and organizations for demanding terrain.

Durability Longevity:

The G-Class is renowned for its durability and longevity, with many vehicles from this era still in service and highly sought after.