IllustrationFAULTY HARMONIC BALANCER IN FLY WHEEL 1999 ML 320, 66,000 MILES NHTSA ACTION NO.PE03058. *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
Engine And Engine Cooling complaints
35 reportsTHE VEHICLE VIBRATED UNCONTROLLABLY WHILE DRIVING. THE DRIVER HAD DIFFICULTY TO MAINTAIN CONTROL OF THE VEHICLE. HOWEVER, THE DRIVER WAS ABLE TO PULL OVER AND THE VEHICLE WAS TOWED TO THE DEALER FOR INSPECTION. THE MECHANIC INFORMED THE DRIVER THAT THE PULLEY ASSEMBLY NEEDED TO BE REPLACED. PLEASE PROVIDE FURTHER DETAILS. …
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THE VEHICLE VIBRATED UNCONTROLLABLY WHILE DRIVING. THE DRIVER HAD DIFFICULTY TO MAINTAIN CONTROL OF THE VEHICLE. HOWEVER, THE DRIVER WAS ABLE TO PULL OVER AND THE VEHICLE WAS TOWED TO THE DEALER FOR INSPECTION. THE MECHANIC INFORMED THE DRIVER THAT THE PULLEY ASSEMBLY NEEDED TO BE REPLACED. PLEASE PROVIDE FURTHER DETAILS. *LA
(1)VEHICLE WAS MAKING A LEFT HAND TURN AND BECAME ALMOST IMPOSSIBLE TO TURN STEERING WHEEL. (2) CRANKSHAFT DAMPENER BECAME SEPARATED AT POINT OF RUBBER VULCANIZED AND CAUSED SERPENTINE BELT TO COME LOOSE LEAVING POWER STEERING TO STOP WORKING ALONG WITH ALL OTHER PULLEYS RUN BY THE SAME BELT. (3) DAMPENER AND BELT WERE REPLACED.…
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(1)VEHICLE WAS MAKING A LEFT HAND TURN AND BECAME ALMOST IMPOSSIBLE TO TURN STEERING WHEEL. (2) CRANKSHAFT DAMPENER BECAME SEPARATED AT POINT OF RUBBER VULCANIZED AND CAUSED SERPENTINE BELT TO COME LOOSE LEAVING POWER STEERING TO STOP WORKING ALONG WITH ALL OTHER PULLEYS RUN BY THE SAME BELT. (3) DAMPENER AND BELT WERE REPLACED. (OLD PARTS ARE AVAILABLE) THIS IS AN EXTREMELY DANGEROUS SITUATION THAT MY LOCAL DEALERSHIP SAYS IS HAPPENING VERY FREQUENTLY. NEW TYPES OF REPLACEMENT DAMPENERS HAVE BEEN CHANGED SIX (6) TIMES IN THE LAST FIVE (5) YEARS IN THE PARTS BOOK. SEVERAL LOCAL MECHANICS SAY IT'S A VERY COMMON PROBLEM AND THEY WONDER WHY A RECALL HAS NOT BEEN ORDERED. IT WOULD BE VERY EASY TO FIND OUT HOW MANY CRANKSHAFT DAMPENERS HAVE BEEN ORDERED AND REPLACED BY BOTH DEALERS AND PARTS SALES. AGAIN, LET ME SAY THIS IS A VERY DANGEROUS SITUATION THAT IS VERY COMMON. MY PRIMARY WORRY IS THAT A SMALL PERSON WOULD NOT BE ABLE TO TURN THE STEERING WHEEL IF THE POWER STEERING GOES OUT AS IN THESE BROKEN DAMPENER CASES. I'M A 225 LB MAN AND I COULD BARELY BRING THE CAR TO A SAFE STOP AT ONLY 25 MILES PER HOUR. WHAT WOULD HAVE HAPPENED ON A MOUNTAIN ROAD? PLEASE INVESTIGATE THIS PROBLEM FOR EVERYONE'S SAFETY. THANK YOU!! *LA
FUEL GAUGE DOES NOT READ CORRECTLY/RUN OUT OF FUEL/ENGINE QUITS LOSS OF CONTROL, POWER BRAKES AND STEERING MAY LEAD TO CRASH/DEFECT *LA
WHILE DRIVING 30 MPH THE VEHICLE'S ENGINE STALLED WITHOUT WARNING. PLEASE PROVIDE ADDITIONAL INFORMATION. *JB
I HAD TO REPLACE THE HARMONIC BALANCER, AND THE MAIN DRIVE SHAFT BEARING ON A 1999 ML MERCEDES WITH THE V-6 MOTOR VIN [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). *TR
HARMONIC BALANCER FAILURE. *AK
CRANKSHAFT PULLEY FAILURE. *AK
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
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.