Problems · NHTSA complaints

1997 Mitsubishi Diamante problems

Owners filed 34 complaints about the 1997 Mitsubishi Diamante with NHTSA between Aug 1997 and Jul 2008. The most-cited component is service brakes, hydraulic (13).

Complaints
34
Filed with NHTSA
Crashes
2
Reported by owners
Fires
1
Reported by owners
Injuries
1
People reported injured
Deaths
0
Reported to NHTSA
01 —By component

Complaints by component

One complaint can cite several components
  1. Service brakes, hydraulic13
  2. Power train10
  3. Engine and engine cooling4
  4. Visibility3
  5. Fuel system, gasoline3
  6. Tires2
  7. Seat belts2
  8. Electrical system2
  9. Parking brake2
  10. Vehicle speed control2
  11. Structure1
  12. Steering1
  13. Service brakes, air1
  14. Latches/locks/linkages1

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

Data from NHTSA Complaints API · synced Oct 30, 2026NHTSA vehicle page
02 —Trend

When complaints were filed

Does it get worse with age? Complaints per calendar year filed
View as table
Model yearComplaints filed per calendar year
19972
199811
19995
20006
20013
20021
20030
20040
20052
20060
20071
20083

Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.

03 —Owner reports

Top problems in owners’ words

Verbatim from NHTSA complaints, newest first

Service brakes, hydraulic

13 reports1 crash
“I PURCHASED THIS VEHICLE 2 MONTHS AGO AND HAVE MADE 5 TRIPS BACK TO THE DEALER DUE TO BRAKES, TIRES & ENGINE TAPPING AND NOW THE TRANSMISSION SEEMS TO BE SLIPPING. *AK (DOT NUMBER: N/A TIRESIZE: P21560R16)”
Owner complaint to NHTSAFiled Sep 17, 2001Service brakes, hydraulic, Engine and engine cooling, Power train, TiresODI 752292

Power train

10 reports1 crash
“SAFETY - TRANSMISSION: AT 9,500 MILES MY CAR STARTED LURCHING WHEN STEPPING ON THE GAS FROM A STOP. IT SUPPOSEDLY WAS REPAIRED BUT HAS CONTINUED TO BE PROBLEM AND EACH TIME I BRING IT IN FOR SERVICE THE DEALER CAN NOT RECREATE THE PROBLEM. SINCE I HAD NOT HEARD THAT THIS HAS BEEN ON GOING PROBLEM WITH THIS MODEL, I THOUGHT IT MUST BE SOMETHING THAT I HAD DONE. UPON REVIEWING THE INFORMATION OF NHSTA, I REALIZE THAT THE DEALERS AND MITSUBISHI ARE DELIBERATELY HIDING THIS PROBLEM. SAFETY - FUEL TANK: MY FUEL TANK BEGAN LEAKING AT 59,560 MILES AND WHEN THE DEALER REMOVED IT HAD 3 STRESS WHOLES. THE TANK HAD TO BE SENT OUT FOR WELDING. OF COURSE, I HAD TO PAY FOR THE REPAIR EVEN THOUGH I SPOKE DIRECTLY TO THE MITSUBISHI COMPLAINT DEPARTMENT. SINCE IT WAS NOT A RECALL ITEM, MITSUBISHI OR THE DEALER WILL NOT PAY FOR THE REPAIR. THE DANGEROUS FUEL LEAK IS ANOTHER ONGOING HIDDEN PROBLEM. ALTERNATOR PULLEY: HAS BEEN MAKING NOISE FROM THE BEGINNING AND I HAVE COMPLAINED EACH SERVICE. NOW, I DISCOVER THROUGH NHTSA THAT ALTERNATOR PULLEY IS A KNOWN DESIGN FLAW. MITSUBISHI AND THEIR DEALERS MUST BE HELD ACCOUNTABLE.*AK”
Owner complaint to NHTSAFiled Feb 22, 2002Fuel system, gasoline, Power trainODI 758506

Engine and engine cooling

4 reports
“THERE IS A MAJOR PROBLEM WITH THE MITSUBISHI DIAMANTE HEATER CORE GOING OUT. MINE WENT OUT A FEW DAYS AGO AND WAS INFORMED BY MITSUBISHI IT WILL COST ME 965 TO REPLACE. EVEN THOUGH THERE ARE HUNDREDS OF MITSUBISHI DIAMANTE OWNERS COMPLAINING ABOUT THIS PROBLEM INCLUDING WITH PEOPLE THAT HAVE AS LOW AS 30-45K ON THEIR VEHICLE. PLEASE LOOK AT THIS FORUM WHICH SHOW MANY MITSUBISHI OWNERS COMPLAINING ABOUT THEIR VEHICLE.. HTTP://WWW.DIAMANTEOWNERS.COM/FORUM/LOFIVERSION/INDEX.PHP?T3615-0.HTML PLEASE HELP ME AND HELP THESE POOR OWNERS. RECALL THIS MAJOR ERROR MISTUBISHI KNOWS ABOUT BUT REFUSES TO DO ANYTHING ABOUT IT AND KEEP SILENT. THIS ALSO CAN CAUSE DEATH BECAUSE WHEN THE HEATER CORE FAILS IT LEAKS AND CAUSES A BAD ODOR OF ANTIFREEZE. YOU WOULDN'T WANT YOUR KIDS BREATHING ON THAT WOULD YOU. ON THE WEBSITE I HAVE PROVIDED YOU IT WILL SHOW A CASE IN WHICH A PERSON WENT INTO RESPIRATORY FAILURE DO TO INHALING ANTI FREEZE.. MANY OF THESE OWNERS TILL THIS DAY FACE A DANGER BECAUSE THEY HAVE NO CHOICE BUT TO DRIVE THESE VEHICLES AS IT IS THERE ONLY MEANS OF TRANSPORTATION AND MANY CANNOT AFFORD TO FIX THIS EXPENSIVE PROBLEM (COSTING AS MUCH AS 1,300). WE BEG OF ALL THE…”
Owner complaint to NHTSAFiled Jan 21, 2008Engine and engine coolingODI 10215505

Visibility

3 reports
“TL*THE CONTACT OWNS A 1997 MITSUBISHI DIAMANTE. THE CONTACT STATED THAT THE RADIATOR LEAKED DUE TO THE HEATER CORE. THE RADIATOR LEAKED ONTO THE CARPET WHEN THE HEAT WAS ACTIVATED. THE CONTACT STATED THAT HE AND HIS FAMILY HAVE INHALED TOXIC FUMES FROM THE RADIATOR LEAKING ONTO THE CARPET AND THEY ARE CONCERNED OF FUTURE HEALTH RISKS. IN ORDER TO REPAIR THE LEAK, THE ENTIRE DASHBOARD HAD TO BE REMOVED. THE VIN WAS UNAVAILABLE. THE CURRENT MILEAGE WAS 113,000 AND FAILURE MILEAGE WAS 112,000.”
Owner complaint to NHTSAFiled Feb 11, 2008VisibilityODI 10217732

Fuel system, gasoline

3 reports1 fire
“DT: CONSUMER HAD 1997 MITSUBISHI DIAMANTE. CONSUMER TOOK VEHICLE TO DEALER,. VEHICLE HAD A GAS LEAK, DEALER COULD NOT FIND HOLE IN GAS TANK, CONSUMER REPLACED GAS TANK, ABOUT 8 MONTHS AFTER GAS TANK WAS REPLACED THE VEHICLE EXPLODED. *AK”
Owner complaint to NHTSAFiled Jun 9, 2005Fuel system, gasolineFire reportedODI 10124674

Tires

2 reports1 crash
“TL*THE CONTACT OWNS A 1997 MITSUBISHI DIAMANTE. THE VEHICLE HAS COOPER LIFELINER CLASSIC II TIRES, SIZE 115/60/15. WHILE DRIVING APPROXIMATELY 70 MPH, THE REAR DRIVER'S SIDE TIRE SPONTANEOUSLY BLEW OUT. THE CONTACT LOST CONTROL OF THE VEHICLE AND CRASHED. THE VEHICLE WAS COMPLETELY DESTROYED AND A POLICE REPORT WAS FILED. PRIOR TO THE CRASH, SHE NOTICED THAT THE TIRE PRESSURE WAS NORMAL AND THAT THE TREAD DEPTH WAS 8/32. AFTER INSPECTING THE TIRE, AN OFFICER CONCLUDED THAT THE TREAD WAS DEFECTIVE BECAUSE CHUNKS OF THE TREAD WERE MISSING AND WIRES WERE HANGING OUT OF THE TIRES. THE CONTACT HAS PICTURES OF THE FAILED COMPONENT. THE TIRE FAILURE MILEAGE WAS 13,000. THE VEHICLE FAILURE MILEAGE WAS 151,000. UPDATED 09/10/08 *BF UPDATED 09/16/08. *JB”
Owner complaint to NHTSAFiled Jul 7, 2008TiresCrash reportedODI 10233373
Data from NHTSA Complaints API (owner reports, unverified) · synced Oct 30, 2026

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.