2004 Mitsubishi Diamante Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2004 Mitsubishi Diamante, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Powertrain (other)266.7%
- Transmission133.3%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
THE DIAMANTE HAS AN ODD ISSUE WHERE THE VEHICLE WILL NOT SHIFT GEARS CORRECTLY WHICH AN EXTREMELY DANGEROUS ISSUE FOR DRIVERS. THE INFORMATION BOARD SHOWS THE TRANSACTION RAPIDLY SWITCHING FROM NEUTRAL TO DRIVE EXCESSIVELY. I HAVE HAD MULTIPLE MECHANIC SHOPS LOOK INTO THIS ISSUE FROM TRANSMISSION SPECIALISTS, TO ELECTRICAL SPECIALIST AND HAVE HAD NO POSITIVE RESULTS.
THE MAIN ISSUE SEEMS TO BE A MANUFACTURING DEFECT IN THE WAVE/CUSHION SPRING LOCATED IN THE TRANSMISSION. MITSUBISHI HAS DESIGNED THE WAVE SPRING AS A FRAGILE TWO COIL PIECE WHICH HAS BEEN KNOWN TO REPEATEDLY BREAK CAUSING CATASTROPHIC FAILURE IN THE TRANSMISSION. THIS IN TURN POSES A THREAT ON THE DRIVER AND PASSENGERS. WHEN THIS WAVE SPRING BREAKS, ACTUAL PIECES OF THE WAVE SPRING MAKE IT THROUGH MITSUBISHIS ALSO FAULTY TRANSMISSION FILTER AND LODGE THEMSELVES IN THE PUMP GEAR, CAUSING THE GEAR TO ACTUALLY BREAK. AFTER THE PUMP GEAR HAS BEEN BROKEN INSIDE THE TRANSMISSION, ALL FORWARD AND REVERSE GEARS IMMEDIATELY STOP FUNCTION AND IN MOST INSTANCES THE VEHICLE SHUTS OFF. THIS COULD RESULT IN POTENTIAL HARM OR EVEN DEATH OF THE DRIVER AND/OR PASSENGER AS THE VEHICLE LOSES ALL MOVING POWER WHICH CAN CAUSE AN ACCIDENT WITH OTHER VEHICLES ON THE ROAD. MITSUBISHI HAS RECENTLY CREATED AN UPDATED VERSION OF THE WAVE SPRING WITHOUT ISSUING A RECALL, WHICH NOW IS A ONE PIECE INSTEAD OF THE COIL SETUP AND HAS A LESS CHANCE OF BREAKING.THIS UPDATE WAS DISCOVERED AFTER THEY I HAD MY VEHICLE IN A TRANSMISSION SHOP WITH A HEFTY BILL TO PAY ($3,700) EVEN THOUGH IT WAS MITSUBISHIS FAULT FOR ENGINEERING A FAULTY PART IN THEIR TRANSMISSION. ALL ONE PERSON WOULD NEED TO FIND OUT ABOUT THIS ISSUE IS SEARCH THE INTERNET WITH THE TRANSMISSION CODE (F4A51) AND THIS ISSUE IS WELL DOCUMENTED, EVEN RESEARCHED BY TRANSMISSION DIGEST (A SPECIALTY MAGAZINE). NOT ONLY IS THIS A LARGE INCONVENIENCE, IT IS ALSO A HAZARD TO ONES LIFE. MITSUBISHI SHOULD RECALL ALL VEHICLES WHICH CONTAIN THE F4A51 AUTOMATIC TRANSMISSION TO PERFORM THE WAVE SPRING AND FILTER UPDATE OR REIMBURSE THOSE, LIKE MYSELF, WHO HAVE ALREADY HAD IT DONE AT MY COST. *TR
Too few reports in this category for a page of its own — they appear in the full complaint list.
Transmission
Reports naming the automatic or manual transmission, including shifting behaviour, shudder, slipping and transmission control modules.
From owner reports, verbatim
CPSC#I11B0131A. 2004 MITSUBISHI DIAMANTE. F4A51 AUTOMATIC TRANSMISSION FAILURE. *LN THE CONSUMER STATED SHE HAS CONCERNS WITH THE SAFETY AND RELIABILITY OF MITSUBISHI AND DODGE VEHICLES AND THEIR OWNERS THAT HAVE THE MITSUBISHI F4A51 AUTOMATIC TRANSMISSION IN CERTAIN MAKE/MODELS. THE MAIN ISSUES SEEMED TO BE A MANUFACTURING DEFECT IN THE WAVE/CUSHION SPRING LOCATED IN THE TRANSMISSION DESIGNED THE WAVE SPRING AS A FRAGILE TWO COIL PIECE WHICH HAS BEEN KNOWN TO REPEATEDLY BREAK CAUSING CATASTROPHIC FAILURE IN THE TRANSMISSION. WHEN THE WAVE BREAKS, ACTUAL PIECES OF THE WAVE SPRING MAKE IT THROUGH MITSUBISHI'S ALSO FAULTY TRANSMISSION FILTER AND LODGE THEMSELVES IN THE PUMP GEAR,CAUSING THE HEAR TO ACTUALLY BREAK. AFTER THE PUMP GEAR HAS BEEN BROKEN INSIDE THE TRANSMISSION, ALL FORWARD AND REVERSE GEARS IMMEDIATELY STOP FUNCTIONING AND IN MOST INSTANCES THE VEHICLE SHUTS OFF. THE CONSUMER STATED SHE HAD THE F4A51 AUTOMATIC TRANSMISSION IN HER VEHICLE, WHICH HAD TO BE REPLACED. *JB
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .