Market Segment:
Full-size Luxury Sedan
Target Audience:
Affluent individuals seeking prestige, comfort, safety, and advanced technology.
Key Competitors 1995:
BMW 7 Series (E38), Lexus LS 400, Audi A8 (D2), Jaguar XJ Series
Vehicle Key Features:
Exceptional build quality, plush interior, advanced suspension for ride comfort, powerful inline-six engine, robust safety features, quiet cabin, pioneering technologies for its era.
Manual Value:
Essential resource for owners and technicians to maintain and repair the complex systems of the 1995 Mercedes-Benz S320, ensuring longevity and optimal performance.
Systems Covered:
Engine, Fuel System, Ignition System, Cooling System, Lubrication System, Exhaust System, Clutch, Manual Transmission, Automatic Transmission, Driveshaft, Differential, Axles, Suspension (Front and Rear), Steering, Brakes (Hydraulic, ABS), Body, Electrical System (Wiring Diagrams, Components), HVAC, SRS Airbag System, Security System, Diagnostic Procedures, Troubleshooting
Approximate Page Count:
1500+
Manual Type:
Factory Authorized Service & Repair Manual
Powertrain Components:
Engine mechanical, cylinder head, block, crankshaft, pistons, connecting rods, camshafts, valve train, fuel injection system (Bosch KE-Jetronic/HPE), ignition timing, emission control systems, cooling system operation, lubrication system, exhaust manifold, catalytic converter
Drivetrain Components:
Clutch operation and adjustment, manual transmission overhaul and repair, 4-speed automatic transmission (722.4) overhaul and repair, driveshaft universal joints, rear axle assembly, wheel bearings, CV joints
Chassis Components:
Front and rear suspension systems (independent, multi-link), shock absorbers, springs, control arms, anti-roll bars, steering system (recirculating ball, power steering pump), brake system (front ventilated discs, rear discs, ABS/ASR operation, hydraulic components)
Electrical And Electronics:
Complete wiring diagrams, starter system, charging system (alternator), battery, lighting (headlights, taillights, interior), ignition switch, power windows, power seats, mirrors, central locking, cruise control, instrument cluster functions, diagnostic port (OBD-I compliant with specific Mercedes protocols), SRS airbag system components and troubleshooting, climate control electronics
Maintenance Procedures:
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, differential fluid change, belt inspection and replacement, battery maintenance, tire rotation and pressure checks
Repair And Overhaul:
Engine component replacement (e.g., head gasket, pistons, rings, bearings), cylinder head removal and reassembly, fuel injector testing and replacement, ignition coil replacement, radiator and water pump replacement, starter and alternator replacement, transmission internal component repair, suspension component replacement (bushings, ball joints, tie rods), brake caliper and rotor replacement, power steering system repair, headlight and taillight bulb replacement, window regulator replacement
Troubleshooting And Diagnostics:
Engine performance diagnostics, no-start conditions, cooling system leaks, brake system faults, electrical system malfunctions, HVAC system issues, ABS/ASR warning light troubleshooting, SRS system fault diagnosis, using Mercedes-specific diagnostic tools and procedures
Technical Depth:
Comprehensive, including detailed diagrams, step-by-step instructions, torque specifications, special tool requirements, diagnostic trouble codes (DTCs) and their interpretations, electrical schematics, and component testing procedures. Suitable for professional technicians and advanced DIY enthusiasts.
Engine Type:
Naturally Aspirated, Inline 6-Cylinder
Engine Displacement:
3.2 Liters (3199 cc)
Bore X Stroke:
89.9 mm x 84.0 mm
Compression Ratio:
10.0:1
Valvetrain:
DOHC, 4 valves per cylinder, dual overhead camshafts
Horsepower:
228 hp @ 5500 rpm
Torque:
232 lb-ft @ 3750 rpm
Fuel System Type:
Electronic Fuel Injection (Bosch KE-Jetronic/HPE)
Recommended Fuel:
Premium Unleaded Gasoline (91 Octane or higher)
Cooling System Type:
Pressurized, liquid-cooled with electric fan
Oil Capacity With Filter:
8.0 Liters (8.5 US Quarts)
Recommended Engine Oil:
SAE 0W-30 or 5W-30 Synthetic (API SG or higher)
Transmission Type:
4-Speed Automatic
Transmission Model:
Mercedes-Benz 722.4
Optional Transmission:
N/A for S320 in 1995 (Manual transmission was available on other W140 models but not the S320)
Transmission Features:
Electronic control, multiple shift modes (e.g., Economy/Sport), torque converter lock-up
Automatic Transmission Fluid Type:
MB-Approval 236.2 or 236.7 (Dexron II E compatible)
Automatic Transmission Fluid Capacity:
Approximately 7.5 Liters (7.9 US Quarts) for full fill
NHTSA Crash Test Rating:
Not explicitly rated by NHTSA in the modern sense, but designed to exceed contemporary safety standards.
Active Safety Features:
Anti-lock Braking System (ABS), Acceleration Slip Regulation (ASR) traction control, power-assisted disc brakes all around (front ventilated), automatic locking differentials (optional, but more common on other W140 variants)
Passive Safety Features:
Supplemental Restraint System (SRS) airbags (driver and front passenger), energy-absorbing crumple zones, reinforced safety cage, side-impact protection, seatbelt pre-tensioners, advanced head restraints
Infotainment System:
Original Becker Grand Prix or similar proprietary Mercedes-Benz audio system with cassette player, optional CD changer. Features include AM/FM radio, pre-set stations, tone controls.
Display Technology:
Analog gauges for speedometer, tachometer, fuel, and temperature. Central digital display for odometer, trip meter, and warning indicators.
Driver Assistance Features:
Cruise Control, Automatic Climate Control (with dual-zone capability), Rain-sensing wipers (optional/later models), Parktronic (optional/later models).
Connectivity Features:
N/A by modern standards. Primarily focused on in-car comfort and control. Antenna for radio and cellular phone (optional, early integrated systems).
Convenience Features:
Power windows, power adjustable front seats with memory, heated front seats, power tilt/telescoping steering column, heated exterior mirrors, automatic antenna, interior ambient lighting.
Oil And Filter Change:
Every 7,500 - 10,000 miles or 12 months, whichever comes first (synthetic oil recommended).
Air Filter Replacement:
Every 15,000 - 30,000 miles or as needed based on driving conditions.
Fuel Filter Replacement:
Every 30,000 - 45,000 miles.
Spark Plug Replacement:
Every 30,000 - 40,000 miles (iridium or platinum recommended).
Coolant Replacement:
Every 30,000 - 60,000 miles or 2-4 years.
Transmission Fluid And Filter:
Every 40,000 - 60,000 miles.
Power Steering Fluid Type:
MB-Approval 236.3 (ATF Dexron II equivalent)
Coolant Type:
Ethylene Glycol based, Mercedes-Benz Specification 325.0 (e.g., Zerex G-05 or equivalent blue/green coolant)
Common Issues W140:
Distributor 'O' rings and vacuum lines (oil leaks), head gasket leaks (especially coolant), crankcase ventilation system blockages, idle control valve issues, vacuum line degradation leading to various system malfunctions, door lock actuator failures, window regulator issues, early ABC suspension issues (though not on the S320 as standard), MAF sensor calibration, OVP relay failures (overvoltage protection), CAN bus communication issues (less common on '95 but present in later W140s).
Specific M104 Issues:
Coil pack failures, spark plug wire degradation, oil cooler seals, timing chain tensioner and guide wear over time.
Mercedes Benz Heritage:
Founded on innovation and engineering excellence, Mercedes-Benz has a long history of producing luxury, safety, and performance vehicles since the early 20th century.
W140 Generation:
The W140 generation, introduced in 1991, represented a significant technological leap from its predecessor (W126 S-Class), focusing on increased size, refinement, and advanced features. It was known for its substantial presence and technological sophistication.
Production Years W140:
1991-1998
Manufacturing Location:
Germany
S320 Positioning In Lineup:
The S320 served as the entry-level model within the W140 S-Class lineup, offering the core luxury and technology of the flagship sedan with a more accessible inline-six engine compared to the V8 and V12 variants.
