Years Covered:
1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000
Vehicle Type:
Full-size Sedan / Hardtop Coupe
Chassis Codes:
JDM/International: F11A, F12A, F13A, F15A, F16A, F17A, F25A, F27A, F31A, F36A, F41A, F46A, F47A. North American: JS1 (Sedan), JS2 (Wagon)
Engine Codes Examples:
6G71, 6G72, 6G73, 6G74, 6A12, 6A13
Market Segment:
Luxury Full-size Sedan / Coupe, competing with models like Toyota Crown, Nissan Cedric/Gloria, and American large sedans.
Key Competitors 1990S:
Toyota Avalon/Lexus LS400, Nissan Maxima/Infiniti Q45, Buick Park Avenue, Ford Taurus SHO.
Design Philosophy:
Designed as Mitsubishi's flagship model, emphasizing refinement, advanced technology (for its time), and performance.
Manual Value Proposition:
Provides professional-level repair and maintenance data, enabling significant cost savings on labor and parts.
Digital Advantage:
Digital format allows for easy searching, printing of specific sections, and keeps the user's hands clean compared to physical manuals.
General Coverage:
All Models, Engines, Trim Levels, and Transmission Types within the specified year range.
Estimated Page Count:
Hundreds (Specific number not provided, but described as 'hundreds of pages of diagrams and detailed information')
Manual Type:
Workshop Repair Service Manual
Engine Service Repair:
Comprehensive diagnosis, repair, and maintenance of engine components, including fuel injection, cooling, and emissions.
Transmission Service Repair:
Detailed procedures for both automatic and manual transmissions, including overhaul and diagnostics.
Brake System:
Repair and maintenance of hydraulic and electronic brake systems, including ABS if equipped.
Electrical System And Wiring Diagrams:
Detailed wiring diagrams, component locations, and diagnostic procedures for all electrical systems.
Suspension And Steering:
Information on diagnosing and repairing suspension components, steering systems, and alignment procedures.
Chassis And Body:
Body repair, structural information, and chassis component service.
Heating Air Conditioning And Emission Systems:
Service and repair of HVAC systems and emission control devices.
Restraint System:
Information related to airbags and seatbelt systems.
Interior Systems:
Service and repair related to interior components.
Differential Drive And Axle:
Service and repair of driveline components, including differentials and axles.
Maintenance:
General maintenance, periodic lubrication, fluid checks, and filter replacements.
Troubleshooting:
Comprehensive diagnostic charts and procedures for identifying and resolving common and complex issues.
Repair:
Detailed, step-by-step repair procedures for all major vehicle systems.
Disassembly And Assembly:
Instructions for removing, overhauling, and reinstalling components.
Electrical Diagnostics:
Specific procedures for diagnosing electrical faults, including use of wiring diagrams.
Depth:
Professional Technician Level: Covers everything from basic maintenance to complex component overhauls and advanced diagnostics, mirroring what is used in official service shops.
Engine Variants Common:
3.0L V6 (6G72), 3.5L V6 (6G74), 2.5L V6 (6A12), 2.5L V6 (6A13 - JDM).
Horsepower Range Typical:
Approx. 160 HP to 230 HP depending on engine and market.
Torque Range Typical:
Approx. 180 lb-ft to 240 lb-ft depending on engine.
Fuel Delivery:
Electronic Fuel Injection (EFI) across most variants.
Standard Transmission Type:
Often a 4-speed or 5-speed automatic transmission (e.g., F4A42, F5A51).
Optional Transmission Type:
Manual transmissions were available on some lower trims or JDM models (e.g., 5-speed manual).
Transmission Features:
Some models featured an adaptive transmission control or Sportronic (sequential shift) mode in later years.
Safety Features Overview:
Variable across years and markets, but generally included front airbags, ABS, and 4-wheel disc brakes on higher trims.
ABS Availability:
Available, especially on higher trim levels and later model years.
Airbag Availability:
Driver and passenger front airbags became standard or widely available during the production run.
Oil Change Interval:
Typically every 3,750 to 5,000 miles (6,000 to 8,000 km) or 6 months, depending on driving conditions and oil type specified in the manual.
Timing Belt Replacement:
Crucial for V6 engines; typically recommended every 60,000 to 90,000 miles (96,000 to 145,000 km) or 5-7 years. The manual will provide precise intervals and procedures, including replacement of tensioners and idler pulleys.
Engine Oil Specification:
Refer to the manual for specific viscosity (e.g., 5W-30, 10W-30) and API service classification. Typically API SJ or higher for later models.
Transmission Fluid Type:
Automatic Transmission Fluid (ATF) specific to Mitsubishi specifications (e.g., Diamond ATF SP-III for later models, or earlier equivalent). Manual transmission fluid type will also be specified.
Coolant Specification:
Ethylene glycol-based coolant with appropriate corrosion inhibitors, typically a 50/50 mix with distilled water. Specific type (e.g., Long Life Coolant) will be detailed.
Brake Fluid Specification:
DOT 3 or DOT 4 brake fluid is typically recommended. The manual will specify the exact type.
Common Problems V6 Engines:
Head gasket leaks, valve stem seals, timing belt failure (if not replaced on schedule), and oil leaks can be common issues.
Automatic Transmission Issues:
Hesitation, slipping, or harsh shifting could indicate issues with valve bodies, solenoids, or fluid degradation. TCM (Transmission Control Module) issues are also possible.
Electrical System Issues:
Corroded grounds, failing sensors (e.g., crank/cam position sensors), and intermittent issues with power windows or climate control can occur over time.
Suspension And Steering Issues:
Worn ball joints, tie rod ends, bushings, and struts can lead to noise, poor handling, and premature tire wear. Power steering leaks are also possible.
Mitsubishi Positioning:
Mitsubishi positioned the Diamante as its flagship luxury sedan, aiming to compete with established luxury marques.
Generations:
Two generations: First generation (1990-1996, developed from the Sigma/3000GT platform) and Second generation (1997-2005, distinct platform).
Production Location:
Primarily produced in Japan.
