NHTSA lists 2 safety recalls and 23 owner complaints for the 1999 Mitsubishi Diamante. Most complaints involve visibility (10) and suspension (3). The EPA rates it 18 mpg combined.
CERTAIN PASSENGER VEHICLES FAIL TO CONFORM TO THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 208, 'OCCUPANT CRASH PROTECTION.' THE BILINGUAL ENGLISH/SPANISH REMOVABLE AIR BAG WARNING LABELS AFFIXED TO THE DASH AND TO THE SUNVISOR DO NOT MEET THE SIZE REQUIREMENTS OF THE STANDARD.
VEHICLE DESCRIPTION: PASSENGER VEHICLES. THE HEAD OF THE SCREW THAT HOLDS THE RETAINING CLIP FOR THE PARKING BRAKE SHOE CAN BECOME BRITTLE AND BREAK OFF.
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
“TL*THE CONTACT OWNS 1999 MITSUBISHI DIAMANTE. THE CONTACT STATED THAT WHILE TRAVELING AT VARIOUS SPEEDS THE REAR VIEW MIRROR WOULD SHAKE; AND WAS NOT SECURELY ATTACHED TO THE WINDSHIELD. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER WHO STATED THAT THE REAR VIEW MIRROR WAS ATTACHED PROPERLY. ON A SEPARATE OCCASION THE REARVIEW MIRROR BROKE AND DETACHED FROM THE WINDSHIELD. THE REAR VIEW MIRROR WAS REPLACED BY AN AUTHORIZED DEALER. THE CONTACT DETECTED THE PROBLEM SINCE THE PURCHASE DATE OF THE VEHICLE. THE FAILURE MILEAGE WAS 200. THE VIN WAS UNAVAILABLE.”
“"TAKATA RECALL" I FOUND THE MOST RECENT RECALL ON THE PAGE, HTTPS://DRIVING-TESTS.ORG/VIN-DECODER/ WHEN I TRY TO KNOW MORE ABOUT VIN NUMBER WAS. I SEARCHED IN GOOGLE SEARCH. AND THAT WHY I FOUND THIS INFORMATION. THANS A LOT FOR YOUR HELP. THE VEHICLE WAS IN MOTION.”
“I OWN A MITSUBISHI DIAMANTE, 1999. I NOTICED FUMES COVERING THE PASSENGER SIDE WINDSHIELD. IN THE WINTER TIME THE PROBLEM IS WORSE AND IT COVERS BOTH PASSENGER SIDE AND DRIVER'S SIDE CREATING VERY DANGEROUS DRIVING CONDITIONS. *TR”
Towing, payload and dimensions aren’t in the EPA or NHTSA data, so we don’t list them.
| Version | City | Hwy | Comb. | Fuel / yr | CO₂ g/mi |
|---|---|---|---|---|---|
| Diamante Auto 4-spd, 6 cyl, 3.5 L · Front-Wheel Drive | 16 | 22 | 18 | $4,200 | 494 |
| Item | Miles | Time | Note |
|---|---|---|---|
| Engine oil & filter | 5,000–10,000 mi | 6–12 months | Follow the oil-life monitor if fitted |
| Tire rotation | 5,000–7,500 mi | Every oil change | Check pressure monthly |
| Engine air filter | 15,000–30,000 mi | 1–2 years | Sooner in dusty areas |
| Cabin air filter | 15,000–25,000 mi | 1–2 years | |
| Brake fluid | — | 2–3 years | Absorbs moisture over time |
| Coolant | 60,000–100,000 mi | 5–10 years | Long-life coolants last longer |
| Spark plugs | 60,000–100,000 mi | — | Iridium/platinum plugs at the long end |
| 12V battery | — | 3–5 years | Heat shortens battery life |
2 safety recalls as of Nov 14, 2026, according to NHTSA. Recall repairs are free at a dealer. Check your VIN to see whether your car is included and whether the repair was done.
Owners filed 23 complaints with NHTSA. The most-cited components are visibility (10), suspension (3), engine and engine cooling (3). Complaints are unverified owner reports and aren't adjusted for how many cars were sold.
The EPA rates the 1999 Mitsubishi Diamante at 18 mpg combined, depending on engine and drivetrain (1 version rated).