2012 Toyota Sienna Powertrain (other) Problems

Rear axle coupler assembly (part number 41303-28013) making very loud noise and vibration.

NHTSA ID

11518928

Incident

Mar 10, 2023

The contact owns a 2012 Toyota Sienna. The contact stated that the rear differential was making an abnormal whirling and grinding sound. There were no warning lights illuminated. The contact called the local dealer but the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to NHTSA. The approximate failure mileage was 79,000.

NHTSA ID

11461296

Incident

Mar 22, 2022

Mileage

79,000 mi

Vehicle began 'whirring' metal noise from underneath. Local mechanic said it was coming from rear differential. I took it to a Toyota dealer, they said rear differential coupler needs replacing ($2159) and drive shaft ($992). It seems the bearing ring inside this sealed unit has failed. Noise is continuous while driving, concern of part failure - we are taking vehicle on family vacation. Researching on - line it appears to be common problem with the Sienna's. Toyota had same issue with RAV 4's and issued recall but have not for the Sienna's. I called Toyota corporate in TX (got up 3 levels) to no avail, and it curt tone, they said they cannot help. Based on other similar stories on line from other Sienna owners, this seems to be a common very expensive design flaw problem with this vehicle.

NHTSA ID

11426247

Incident

Jun 24, 2021

MY 2012 TOYOTA SIENNA RECENTLY BEGAN MAKING A LOUD WHINING NOISE FROM THE REAR AXLE AREA. UPON INSPECTION, WE WERE INFORMED THAT THE DIFFERENTIAL UNIT WAS FAILING AND NEEDED TO BE REPLACED. THIS WOULD COST US BETWEEN $2,500-$3,000. AFTER SOME RESEARCH, I DISCOVERED THAT THIS IS A COMMON PROBLEM WITH THE SIENNA, LIKELY CAUSED BY A DESIGN FLAW. THE SAME UNIT WAS USED ON THE RAV-4, AND AFTER SIMILAR PROBLEMS SURFACED IT WAS RECALLED AND FIXED BY TOYOTA. GIVEN THE DANGER POSED BY FAILURE OF THIS PART TO A FAMILY VEHICLE, AND THE KNOWN EXISTENCE OF THE PROBLEM BY TOYOTA, IT SEEMS OBVIOUS THAT IT SHOULD BE IMMEDIATELY RECALLED AND FIXED BY THE MANUFACTURER.

NHTSA ID

11365250

Incident

Sep 1, 2020

Mileage

95,000 mi

SERVICE TECH AT THE TOYOTA DEALER SAID MY ELECTROMAGNETIC COUPLER / VISCOUS COUPLER AND DRIVESHAFT UJOINT SEIZED. AFTER FURTHER RESEARCH ONLINE IT SEEMS ITS COMMON. WONDERING IF TOYOTA WOULD PUT OUT A RECALL?

NHTSA ID

11351737

Incident

Aug 27, 2020

Mileage

119,647 mi

UNIT IS PRODUCING A SPEED DEPENDENT WHINE FROM THE REAR DIFFERENTIAL CONSISTENT WITH A BEARING FAILURE IN THE VISCOUS COUPLER. ISSUE FIRST OBSERVED WITH APPROXIMATELY 98,000 MILES ON ODOMETER. THIS APPEARS TO BE A COMMON COMPONENT FAILURE ON MANY TOYOTA AWD VEHICLES MANUFACTURED IN THE LAST 15-20 YEARS, AND THE COMPONENT IN QUESTION MAY BE UNDER-ENGINEERED TO PERFORM AS EXPECTED IN NORMAL DRIVING CONDITIONS. REPLACEMENT PART COSTS $1300+ FROM TOYOTA, NOT INCLUDING INSTALLATION. *TR

NHTSA ID

11326947

Incident

May 1, 2020

Mileage

98,000 mi

SAYS MY REAR DIFFERENTIAL - VISCOUS COUPLER- IS BAD AND NEEDS TO BE REPLACED AT A COST OOF AT LEAST $1,300 AND THAT DOESN'T INCLUDE INSTALLATION. HAPPENED JUST AS CAR WENT OVER 100,000 MILES AND IS COVERED IN RAV 4 BC HAD SAME PROBLEM BUT NOT 2012 SIENNA NOTHING HAPPENED EXCEPT IT SUDDENLY STARTED NOT BECAUSE OF ANYTHING I DID.

NHTSA ID

11324915

Incident

Jan 2, 2020

Mileage

100,000 mi

THE REAR VISCOUS COUPLER ON THE AWD HAD GONE BAD AND NEEDS REPLACEMENT. THIS PART IS THE SAME DEFECTIVE PART ON THE RAV 4 THAT HAD AN EXTENDED WARRANTY COVERAGE DUE TO BAD DESIGN BUT IS NOT COVERED ON THE SIENNA. THIS PART NEEDS A RECALL.

NHTSA ID

11316397

Incident

Mar 1, 2020

Mileage

118,000 mi

THE BEARING FOR THE VISCOUS COUPLER HAS GONE BAD. IT WHINES LOUDLY WHEN IN MOTION, AND THE VOLUME CORRELATES WITH THE SPEED. ACCORDING TO FEEDBACK FROM ONLINE THIS ISSUE HAPPENS A LOT. TOYOTA WILL NOT CHANGE THE BEARING ($50 PLUS LABOR). THEY WILL ONLY CHANGE THE WHOLE COUPLER ($1800 PLUS LABOR) AS THEY STATE THE COUPLER IS NOT SERVICEABLE. MULTIPLE PEOPLE HAVE SERVICED THE WORKING COUPLER TO CHANGE JUST THE BEARING. TOYOTA RELEASED A SIMILAR TSB FOR THE RAV 4 WHERE THE COUPLER FAILED.

NHTSA ID

11307184

Incident

Aug 1, 2019

Mileage

75,000 mi

MY 2012 SIENNA AWD XLE HAS 103K MILES AND HAS A WHIRRING NOISE COMING FROM THE REAR DIFFERENTIAL AREA FOR A WHILE NOW. THE PITCH AND VOLUME IS PROPORTIONAL TO SPEED AND IS LOUDER AS SPEED INCREASES. MY RESEARCH TELLS ME THIS IS A COMMON DEFECT WITH THE COUPLING BEARINGS IN FRONT OF THE REAR DIFFERENTIAL. IT SEEMS THAT RAV4 OWNERS GOT A RECALL FOR THE SAME ISSUE, BUT SIENNA OWNERS DID NOT. TOYOTA HAS REDESIGNED THIS PART ON LATER MODELS TO AVOID THE ISSUE. HOPE YOU CAN GET THIS RESOLVED. THANKS.

NHTSA ID

11287814

Incident

Nov 19, 2019

Mileage

100,000 mi

FRONT AXLE LEAKING FLUID

NHTSA ID

11197376

Incident

Apr 17, 2019

Mileage

171,000 mi

REAR DIFFERENTIAL HAS FAILED AT ONLY 60K MILES. WELL DOCUMENTED ISSUE FOR AWD SIENNA MODELS YET NO RECALL ISSUED. SAFETY CONCERN FOR THIS FAMILY OF FIVE.

NHTSA ID

11196818

Incident

Apr 10, 2019

WHEN COMING TO A STOP GOING ABOUT 5 MPH TOWARDS A STOP SIGN, MY VAN ACCELERATED INTO TRAFFIC. BECAUSE THE VAN JOLTED ME INTO ONCOMING TRAFFIC, IT ALMOST CAUSED AN ACCIDENT. IT DOESN'T SEEM TO MATTER WHETHER I AM BRAKING OR COASTING, THE VAN WILL ACCELERATE UNCONTROLLABLY.I HAVE TWO CHILDREN AND NOT ONLY AM I PUTTING THEIR LIVES AT RISK, BUT MINE ALSO. I AM NOT ABLE TO DRIVE THIS VEHICLE DUE TO HOW DANGEROUS IT IS.

NHTSA ID

11175789

Incident

Feb 8, 2019

Mileage

99,000 mi

REAR DIFFERENTIAL COUPLER DYSFUNCTIONAL WITHOUT NO REASON. ALL OF THE SIENNA ESPECIALLY AWD ARE SUFFERING FROM THIS ISSUE.TOYOTA DENIES TO COVER IT.

NHTSA ID

11097881

Incident

May 1, 2018

Mileage

47,000 mi

WHILE PARKED, DRIVER BEGAN EXITING VEHICLE AND VAN BEGAN TO ROLL AND CONTINUED TO ROLL WHEN GEAR SHIFT LEVER CONFIRMED IN PARK AND BRAKE CONTINUALLY PRESSED, EVENTUALLY HITTING A HOUSE.

NHTSA ID

11071940

Incident

Feb 1, 2018

Mileage

92,000 mi

ALL UNDERWOOD COMPONENTS ARE NOT ONLY VULNERABLE, BUT ATTRACTIVE TO RODENTS. WHILE PARKED OVERNIGHT ON 4 CONSECUTIVE NIGHTS, RODENTS HAVE CHEWED THROUGH WIRES DESPITE ATTRACTIVE RODENT POISON IN THE ENGINE BAY, THE POISON IS UNTOUCHED AND THE WIRES ARE ATTACKED EVERY NIGHT. TO DATE INJECTOR WIRES, SENSOR SIRES, FUEL PUMP WIRES HAVE BEEN COMPROMISED, INCLUDING SENSORS FOR THE STABILITY CONTROL SYSTEM, WHICH IS DISABLED. I REPAIRED DAMAGE BY RUNNING NEW WIRES, CLEARING NESTS AND SET TRAPS AND POISON, BUT NOW THE THE FUEL SYSTEM HAS BEEN ATTACKED AND THE FUEL PUMP DOES NOT ACTIVATE. 3 OTHER CARS PARKED IN THE SAME LOCATION FOR THE PAST 5 MONTHS ARE UNTOUCHED. SAFETY SYSTEMS ARE LIKELY TO BE COMPROMISED FOR ANY PERSON WHO MUST PARK THESE OUTDOORS.

NHTSA ID

10787185

Incident

Oct 30, 2015

Mileage

79,000 mi

JOINING HIGHWAY IN A SITUATION WHERE VEHICLES GIVING WAY CAUSE HESITATION AND THEN GIVE WAY CAUSING BRAKING THEN ACCELERATION REPEATEDLY, TRANSMISSION REFUSED TO DOWNSHIFT ON KICK DOWN, VEHICLE WOULD NOT ACCELERATE, ACTUALLY SLOWED SIGNIFICANTLY FORCING FOLLOWING VEHICLES TO BRAKE .VEHICLE EVENTUALLY BEGAN TO PICK UP SPEED.GENERALLY POOR RESPONSE FROM TRANSMISSION IN ALL MODES. TRANSMISSION DROPS OUT OF DRIVE AT LOW SPEEDS CAUSING ENGINE TO RACE BEFORE TAKING UP DRIVE, VERY HARD TO OPERATE VEHICLE SMOOTHLY.. EXCESSIVE ENGINE VIBRATION AND NOISE FOR THIS PRICE POINT ,KNOWN MORE REFINED DIESELS KNOCKING FROM STEERING COLUMN ON CONSTANT RADIUS TURNS WHEN MAKING SMALL STEERING CORRECTIONS, DETECTABLE AT LOW AND MODERATE TO HIGH SPEED. *TR

NHTSA ID

10456744

Incident

Feb 15, 2012

Mileage

1,500 mi