IllustrationHARMONIC BALANCER FAILURE. *AK
1999 Mercedes Benz ML320
Owner reports · Recalls · Investigations
More warning signs than most ML320 years
Owner complaints for the 1999 Mercedes Benz ML320 are substantially higher than the model-year median of 28.
About this comparison →How this year compares
Owner complaints by model year
Compare all ML320 years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
50–25K
725–50K
2950–75K
1375–100K
12100–150K
6150K+
72 reports with mileage · 53 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Engine And Engine Cooling. Review the 35 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Steering. Review the 29 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Power Train. Review the 19 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
14 crash reports2 fire reports6 injury reports
What owners actually said
125 reportsAFTER THE VEHICLE WAS SERVICED FOR NHTSA RECALL 03V121000 CONCERNING POWER STEERING PUMP, VEHICLE EXPERIENCED ONGOING STEERING PROBLEMS. CONSUMER STATED WARRANTY EXPIRED, AND DEALER REFUSED TO ADMIT THAT VEHICLE WAS RUNNING IN GOOD CONDITIONS. DEALER CHARGED CONSUMER EVERY TIME VEHICLE WAS BROUGHT IN FOR A STEERING PROBLEM…
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AFTER THE VEHICLE WAS SERVICED FOR NHTSA RECALL 03V121000 CONCERNING POWER STEERING PUMP, VEHICLE EXPERIENCED ONGOING STEERING PROBLEMS. CONSUMER STATED WARRANTY EXPIRED, AND DEALER REFUSED TO ADMIT THAT VEHICLE WAS RUNNING IN GOOD CONDITIONS. DEALER CHARGED CONSUMER EVERY TIME VEHICLE WAS BROUGHT IN FOR A STEERING PROBLEM. *AK
CRANKSHAFT PULLEY FAILURE. *AK
SUN ROOF PARTS FAILED, WIND DEFLECTOR COMPONENTS FAILED WHILE MOON ROOF WAS BEING OPENED. WHEN I TRIED TO CLOSE THE ROOF, IT WOULD NOT DO SO UNTIL I REMOVED THE BENT PART ALONG WITH DEFLECTOR. THIS IS ACTUALLY THE SECOND ISSUE WITH THIS ROOF. IT WAS TAKEN TO THE DEALER WHEN NEW TO GET THE HEIGHT ADJUSTED WITH ROOF LINE.*AK
VEHICLE HAS A FAULTY FUEL PUMP.*MR THE CONSUMER RECEIVED A RECALL LETTER REGARDING THE POWER STEERING, HOWEVER THE CONSUMER DID NOT STATE IF THE VEHICLE EXPERIENCED A FAILURE. *JB *NLM
THE HARMONIC BALANCER ON MY 1999 MERCEDES ML320 ENGINE TYPE M112 FAILED AND RESULTED IN $4,000 TO REPAIR. THE PART FAILED WITH NO ADVANCED WARNING. EVEN THE MERCEDES DEALERSHIP WHO PERFORMED THE POWER STEERING RECALL TWO WEEKS PRIOR TO THE FAILURE DID NOT SPOT ANY PROBLEM AND THEY KNEW TO BE LOOKING. I WAS LUCKY THE FAILURE O…
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THE HARMONIC BALANCER ON MY 1999 MERCEDES ML320 ENGINE TYPE M112 FAILED AND RESULTED IN $4,000 TO REPAIR. THE PART FAILED WITH NO ADVANCED WARNING. EVEN THE MERCEDES DEALERSHIP WHO PERFORMED THE POWER STEERING RECALL TWO WEEKS PRIOR TO THE FAILURE DID NOT SPOT ANY PROBLEM AND THEY KNEW TO BE LOOKING. I WAS LUCKY THE FAILURE OCCURRED IN MY DRIVEWAY BACKING OUT OF THE GARAGE IN STEAD OF ON THE FREEWAY WITH AN IMMEDIATE LOSS OF POWER STEERING OR DESTRUCTION OF THE ENGINE.*AK
CONSUMER COMPLAINED ABOUT HAVING PROBLEMS WITH THE PULLEYS MAKING A HOLE IN THE OIL PAN. MANUFACTURER WAS NOT NOTIFIED AT THE TIME OF THIS CALL.*AK THE VEHICLE HAD AN OIL LEAK. THE TECHNICIAN STATED THE LEAK WAS CAUSED BY A PULLEY WHICH WAS HITTING AGAINST THE OIL PAN. THE TECHNICIAN STATED THAT IF THE OIL PAN WAS RE…
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CONSUMER COMPLAINED ABOUT HAVING PROBLEMS WITH THE PULLEYS MAKING A HOLE IN THE OIL PAN. MANUFACTURER WAS NOT NOTIFIED AT THE TIME OF THIS CALL.*AK THE VEHICLE HAD AN OIL LEAK. THE TECHNICIAN STATED THE LEAK WAS CAUSED BY A PULLEY WHICH WAS HITTING AGAINST THE OIL PAN. THE TECHNICIAN STATED THAT IF THE OIL PAN WAS REPLACED THE PULLEY WILL STILL HIT THE OIL PAN AND CAUSE A LEAK. THE CHECK ENGINE LIGHT ILLUMINATED. THE DEALER REPLACED THE MASS AIR FLOW SENSOR. *PH *NLM
CRANK SHAFT PULLEY WHEEL FLEW OFF. *LA
1999 MERCEDES BENZ ML 320 HAS DEFECTIVE WIND SHIELD WIPER WATER TANKS. THE LACK OF HAVING FLUID TO CLEAR YOUR WINDOW IN ADVERSE WEATHER OR ROAD CONDITIONS COULD CAUSE ACCIDENTS OR DEATH. *LA
DRIVER'S SIDE POWER WINDOW STUCK OR STOPPED WHILE OPERATING. THE CONSUMER WAS INFORMED BY THE DEALER THAT ALL FOUR WINDOW CLUSTERS HAD TO BE REPLACED TO CORRECT THE PROBLEM. ALSO, LOST OF POWER STEERING FLUID. FLUID WAS LEAKING FROM THE HOSES/CLAMPS AND CONNECTORS. DEALER AND MANUFACTURER WERE NOT NOTIFIED AT THIS TIME. *AK…
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DRIVER'S SIDE POWER WINDOW STUCK OR STOPPED WHILE OPERATING. THE CONSUMER WAS INFORMED BY THE DEALER THAT ALL FOUR WINDOW CLUSTERS HAD TO BE REPLACED TO CORRECT THE PROBLEM. ALSO, LOST OF POWER STEERING FLUID. FLUID WAS LEAKING FROM THE HOSES/CLAMPS AND CONNECTORS. DEALER AND MANUFACTURER WERE NOT NOTIFIED AT THIS TIME. *AK THE MANUFACTURER WAS AWARE OF THE PROBLEM BUT DID NOT NOTIFY THE OWNERS. THE CONSUMER WAS INFORMED BY AN INDEPENDENT SHOP. *SCC *JB
Official recalls
0No recalls in this snapshot.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
2PE03058 · Engine Crankshaft Pulley Failure
Opened Dec 17, 2003 · Closed Apr 22, 2004
Status: closed (inferred from source dates) · Engine And Engine Cooling:engine:gasoline:belts And Associated Pulleys
THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED THIS PRELIMINARY EVALUATION TO INVESTIGATE ALLEGATIONS OF ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER FAILURE THAT COULD RESULT IN LOSS OF POWER-STEERING ASSIST.ODI HAS RECEIVED A TOTAL OF 546 NON-DUPLICATIVE REPORTS THAT ALLEGE ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER FAILURE ON ALL MERCEDES-BENZ VEHICLES USING THE SUBJECT COMPONENT.THE SUBJECT COMPONENT FAILURES ARE PROGRESSIVE IN NATURE AND ONLY A SMALL PERCENTAGE OF THE COMPLAINTS AND WARRANT CLAIMS INVOLVED A FAILURE THAT HAD PROGRESSED FAR ENOUGH TO EFFECT POWER STEERING PERFORMANCE (6 OF 55 ODI COMPLAINTS REFERENCE INCREASED STEERING EFFORT).THERE HAVE BEEN NO CRASHES OR INJURIES RELATED TO THE ALLEGED DEFECT.A SAFETY-RELATED DEFECT HAS NOT BEEN IDENTIFIED AT THIS TIME AND FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST.THE AGENCY WILL TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.SEE SUMMARY REPORT ATTACHED FOR FURTHER DETAIL.
PE03006 · Power Steering Hose Assembly Leakage
Opened Feb 13, 2003 · Closed Apr 4, 2003
Status: closed (inferred from source dates) · Steering:hydraulic Power Assist:hose, Piping, And Connections; Steering:hydraulic Power Assist:power Steering Fluid
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.
Additional source detail variants (2)
Steering:hydraulic Power Assist:hose, Piping, And Connections
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.
Steering:hydraulic Power Assist:power Steering Fluid
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.