2018 Toyota Sienna 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 2018 Toyota Sienna, 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)1824.7%
- Fuel system1317.8%
- Electrical68.2%
- Engine56.8%
- Airbags56.8%
- Interior & seats56.8%
- Body & structure56.8%
- Driver assistance56.8%
- Visibility22.7%
- Brakes22.7%
- Other / unspecified22.7%
- Seat belts11.4%
- Steering11.4%
- Suspension11.4%
- Tires & wheels11.4%
- Exterior lighting11.4%
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
Vehicle: 2018 Toyota Sienna XLE AWD, VIN [XXX], approximately 112,000 miles. Component: Power Train / Automatic Transmission (UA80F 8-speed). The vehicle has developed a pronounced whining noise from the transmission that rises with road speed, accompanied by harsh/rough shifting. A Toyota dealer inspected the vehicle and diagnosed a failing transmission requiring replacement. The symptoms and diagnostic trouble codes match those described in Toyota TSB T-SB-0160-18 ("Transaxle Whine Noise, Harsh Shift, MIL ON, or Reduced Power") for the UA80 8-speed transmission. This is the same failure mode Toyota acknowledged in Customer Support Program ZJC, which attributes the defect to a washer/locking tab that was not sufficiently bent during assembly, allowing an internal nut to loosen and causing progressive internal damage. However, this vehicle's transaxle serial number falls outside the range covered by ZJC, so Toyota has not provided coverage despite the identical defect and symptoms. This represents a safety concern. Based on documented failures of this transmission across the UA80 platform, the condition can progress to loss of power, limp mode, or sudden loss of forward propulsion while driving — including at highway speed and without further warning — creating a risk of a crash or of being stranded in traffic. The vehicle has been maintained through authorized Toyota service. I am requesting that NHTSA investigate whether the UA80/UA80F transmission defect warrants a broader safety defect determination and recall, given the volume of similar complaints across affected model years INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Since owning my 2018 Toyota Sienna, I have experienced hesitation and erratic shifting with my transmission. I have the UA80E transmission which upon research others are experiencing issues with as well. It appears Toyota is not fully acknowledging the problem. The problem is a safety issue as sometimes when you go to quickly accelerate (merging, making a turn while starting from a stop, etc) the transmission hesitates and doesn't engage for a few seconds. This is an ongoing problem with the transmission. Toyota really needs to fix these transmissions!
Fuel system
Reports naming fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks.
From owner reports, verbatim
Hi, I’d like to report a serious issue with my 2018 Toyota Sienna related to the recent fuel system recall. Since the repair, the vehicle has leaked all of its gasoline not once, but three separate times. One of those times, my family was inside the vehicle, and the smell of gas was overwhelming. The car wouldn’t start, and it was clearly an unsafe situation. Now the dealership is charging me $1,400 to replace the fuel pressure hose and clamp, which, after thorough research and review, appears to be directly related to the process they followed when replacing the recalled fuel pump. I’ve also tried contacting the service manager, but I haven’t received a call back. That’s why I’m now requesting that Toyota open a formal case to investigate this properly. I believe this repair should be covered, and I’m asking for support from Toyota directly.
When accelerating, both from a stop and/or at speed, there is a definite hesitation. When gas pedal is pressed down, there is a noticeable pause before acceleration begins. This causes safety issues especially when accelerating to merge with moving traffic. Have owned this van since Oct 2021, and it has always been an issue. Possible fuel filter problem. Have not reported issue to dealer. Currently under extended warranty.
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
Odometer Fraud. The contact purchased a 2018 Toyota Sienna. The contact stated that while attempting to register the vehicle, it was discovered that there was a mileage discrepancy. The vehicle was a dealer sale. At the time of purchase, the vehicle mileage was 57,000, and at the time of registration, it was discovered that the mileage was 175,152.
I am an owner of a 2018 Toyota Sienna LE. The Vehicle has an issue with the safety connect system. Dealer first states that the cause is the data handling being off, called Toyota turned it on and waited for a few days and still did not work. Called Dealer to make an appointment for service, dealer advised that they reset the DCM twice and to wait 24-48 hours to see if it works. It still does not work. No lights present on the overheard place where the SOS Safety connect Button is located.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
The contact owns a 2018 Toyota Sienna. The contact stated while driving at an undisclosed speed, the vehicle jerked and lost motive power. In addition, the contact stated that on several occasions the vehicle shut off independently. The vehicle was taken to the dealer; however, the failure could not be duplicated. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. In addition, the contact stated that the vehicle was taken to the dealer several times due to the failure. The contact stated that the failure began in 2019 but had become a persistent failure. The contact stated the vehicle was repaired under of an unknown recall and the fuel pump was replaced in 2020; however, the failure reoccurred. The manufacturer was not made aware of the failure. The failure mileage was unknown.
N
Too few reports in this category for a page of its own — they appear in the full complaint list.
Airbags
Reports naming the air-bag system — deployment behaviour, inflators, sensors and warning lights.
From owner reports, verbatim
The contact owned a 2018 Toyota Sienna The contact stated while driving 70 MPH, the contact was rear-ended and the vehicle lost control and the vehicle rolled over multiple times and fell into a ditch. The contact stated that the side air bags did deploy but the front air bags did not deploy vduring the accident. Medical attention was given to the contact and her family in which they were transported to the local emergency room. The contact stated she and her family suffered injuries the contact stated she had bruised ribs a contusion to her hip and her shoulder and a bruised lung. The contact daughter suffered a concussion neck and shoulder and was diagnosed with manubrium in her back. The contact son suffered a concussion contusion on his abdomen and neck. The contact spouse suffered an injured wrist finger injury and possibly broken ribs and all of the family suffered from whiplash. A police report was filed. The vehicle was towed to a local towing company and the vehicle was released to the insurance to be sent to CO-part. The dealer was contacted and the vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 117,000.
N
Too few reports in this category for a page of its own — they appear in the full complaint list.
Interior & seats
Reports naming seats, latches, locks, linkages and interior fittings.
From owner reports, verbatim
The last week of September 2021 my husband notice a sound like water runing and a leak on the driver and passenger seats, we take the vehicle to the Dealer for an inspection on October 2nd. They said the AC hose was clogged for a spiderweb and the leak can create a mold. This mold can affect my family health. We informed to the insurance and we taked the vehicle to the Dealer for repair. They did an expensive special cleaning to Remove the mold, and disamble my entire vehicle, the worse is my vehicle still unassembled after 3 months at the dealership. All this happens with out any warning sign, symptoms or light. This vehicle is 3 years old and all services on time and by the same Dealership. My vehicle has a lot of technology but not warning about this AC clogged and damage my entire vehicle wich still on repair.
TL* THE CONSUMER OWNS A 2018 TOYOTA SIENNA. THE CONSUMER STATED WHILE THE VEHICLE WAS AT A STAND STILL, WHEN ALL FOUR REAR DRIVER AND PASSENGER SEATS BEGAN TO MOVE INDEPENDENTLY FORWARD. THE VEHICLE WAS TAKEN TO LOCAL DEALER AUTONATION TOYOTA HAYWARD LOCATED AT 24773 MISSION BLVD, HAYWARD, CA 94544, WHERE IT WAS DIAGNOSED WITH NEEDING FLOOR RAIL CAPS TO BE REPLACED. THE VEHICLE HAD BEEN REPAIRED TWICE BUT CONTINUES TO EXPERIENCE THE FAILURE. THE MANUFACTURER HAD BEEN INFORMED OF FAILURE. THE FAILURE MILEAGE WAS 1,000. *DT *AS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Body & structure
Reports naming the vehicle structure, frame, body panels, doors, hood and trim.
From owner reports, verbatim
The last week of September 2021 my husband notice a sound like water runing and a leak on the driver and passenger seats, we take the vehicle to the Dealer for an inspection on October 2nd. They said the AC hose was clogged for a spiderweb and the leak can create a mold. This mold can affect my family health. We informed to the insurance and we taked the vehicle to the Dealer for repair. They did an expensive special cleaning to Remove the mold, and disamble my entire vehicle, the worse is my vehicle still unassembled after 3 months at the dealership. All this happens with out any warning sign, symptoms or light. This vehicle is 3 years old and all services on time and by the same Dealership. My vehicle has a lot of technology but not warning about this AC clogged and damage my entire vehicle wich still on repair.
The front passenger side bumper snap(s) comes undone, by air flow, as vehicle travels down the road - this causes further tearing of the supporting plastic frame. Local Toyota dealership says this initially was caused by a driver of the vehicle hitting a concrete curb. Note: Bottom of the bumper is only 8 inches from ground surface. The safety issue is: the bumper and its supporting plastic frame will eventually break and fall off vehicle while in transport. I have witnessed this several times on other vehicles (especially on Toyota's). Dealer compounds problem by saying entire bumper has to be replaced at high cost to customer. Customer delays repair (as I have). This causes further damage to the supporting plastic frame. I have gone from one snap to several snaps in duration. I sent Corporate Toyota a complaint - Essentially, they said they would not do anything .
Too few reports in this category for a page of its own — they appear in the full complaint list.
Driver assistance
Reports naming forward-collision avoidance, lane keeping, back-over prevention, cruise control and related electronic driver-assistance systems.
From owner reports, verbatim
I HAD TORQUE CONVERTER CLUTCH PRESSURE CONTROL SOLENOID CONTROL CIRCUIT AND WHEN I RICH 85 SPEED THE CAR CHECK AND MY FRIEND HAVE THE SAME CAR SAM MODEL HE HAD THE SAME ISSUE
UNINTENDED ACCELERATION WHILE REVERSING VEHICLE. VAN WENT FULL THROTTLE AND SPED UP IN REVERSE WHILE BACKING UP FROM MY DRIVE WAY AT HOME. *TR
Too few reports in this category for a page of its own — they appear in the full complaint list.
Visibility
Reports naming windshields, glass, wipers, defrosters and mirrors.
From owner reports, verbatim
The contact owns a 2018 Toyota Sienna. The contact stated that while driving at approximately 70 MPH, the sunroof glass exploded without impact while closed. No warning lights were illuminated. The vehicle was taken to a local dealer, where it was diagnosed that the sunroof glass needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was 58,634.
DRIVING ON 1-75 AND SUNROOF EXPLODED. GLASS ALL OVER OUR DOG IN THE BACK. NO TRAFFIC AROUND US THANK GOD. VAN IS 3 DAYS OLD. TOOK TO DEALER IN FLORIDA AFTER DUCT TAPING AROUND HOLE. TOLD IT WAS HIT BY SOMETHING. WE DID NOT HEAR ANYTHING BUT MY CONCERN IS IF WE AROUND ANY TRAFFIC WE MAY NOT BE HERE ANYMORE. HELL OF A NOISE CAUSING ME TO SWERVE. LUCKY NO ONE WAS THERE. TOTAL BILL 1690.85. I AM A FORMER TOYOTA DEALER FROM ONTARIO CANADA. SCARED THE YOU NO WHAT OUT OF US.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Brakes
Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.
From owner reports, verbatim
LIGHT, MODERATE TO TOO MUCH VIBRATION ON THE FRONT BRAKE WHEN DRIVING DOWNHILL. I WAS DRIVING DOWNHILL AND I FELT MODERATE VIBRATION ON THE FRONT BRAKE. I WAS SO SCARED THAT I HAVE TO RELEASE THE BRAKE HOPING TO STOP THE VIBRATION. ON THE WAY BACK HOME, I HAVE TO DRIVE ANOTHER DOWNHILL AND THIS TIME, I FELT TOO MUCH VIBRATION ON THE FRONT BRAKE WHEN I APPLIED THE BRAKE. THE VIBRATION WAS TOO MUCH THAT EVEN THE HOOD, I FEEL LIKE IT STARTS VIBRATING AS WELL. WHEN DRIVING FLAT, THE VIBRATION WILL FADE AWAY OR THERE IS NO VIBRATION AT ALL.
TL* THE CONTACT OWNS A 2018 TOYOTA SIENNA. WHILE DRIVING APPROXIMATELY 45-50 MPH, THE ACCELERATOR PEDAL WAS DEPRESSED, BUT FAILED TO RESPOND. ADDITIONALLY, THE VEHICLE DECELERATED INDEPENDENTLY ON OCCASION. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. LARRY H MILLER TOYOTA COLORADO SPRINGS (LOCATED AT 5115 NEW CAR DR, COLORADO SPRINGS, CO 80923, (719) 419-5832) WAS NOTIFIED OF THE FAILURE. THE CONTACT STATED THAT THE FAILURE RECURRED ON SEVERAL OCCASIONS. THE MANUFACTURER WAS NOT CONTACTED. THE APPROXIMATE FAILURE MILEAGE WAS 10,000. THE CONSUMER STATED THE WHILE BACKING OUT OF A PARKING SPACE, THE VEHICLE SUDDENLY STOPPED REVERSING AND THE ENGINE BEGAN TO REV UP AS IF THE GAS PEDAL WAS BEING DEPRESSED. THE VEHICLE WAS PUT INTO PARK AND BACK INTO REVERSE. THE ISSUE RESOLVED ITSELF. THE BRAKING SYSTEM WOULD SHUTTER WHEN IN SNOW OR ICE CAUSING THE VEHICLE TO VIBRATE VIOLENTLY AND LOSE TRACTION. *JS
Too few reports in this category for a page of its own — they appear in the full complaint list.
Other / unspecified
Reports whose component NHTSA recorded as unknown, or that do not map to one of the categories above.
From owner reports, verbatim
The contact owns a 2018 Toyota Sierra equipped with a Joysceer USA Inc, Hand Control Unit. The contact stated that while operating the vehicle, the message advising to "Stop immediately" was displayed with the error code: 4209 BSM. The contact stated that later a second error code: 1069 SAM was displayed. The contact stated that the messages were due to a malfunction of the Hand Control Unit. The cause of the failures was not yet determined. The manufacturer and installation facility were contacted regarding the failure, but no response was provided. No identifying information was available for the equipment. The failure mileage was 2,000.
ORIGINAL TIRES AT 17K, MY 2018 SIENNA IS SHOWING EXCESSIVE WEAR ON THE OUTSIDE OF THE FRONT TIRES. ALIGNMENT CHECKED, IT IS FINE.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Seat belts
Reports naming seat belts, buckles, retractors and pretensioners.
From owner reports, verbatim
The contact owns a Baby Trend car seat, Model Number: CS661232H-SB-00137, Manufactured Date: 07/05/2021, installed in a 2018 Toyota Sienna. The contact stated that the buckle handle on the left was hard to operate. The contact also stated that the harness connection was defective. The manufacturer was notified of the failure and informed the contact to send the car seat back; however, the contact stated she needed a temporary replacement car seat. The car seat was not repaired nor replaced.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Steering
Reports naming the steering system — racks, columns, power-steering assist and steering linkage.
From owner reports, verbatim
The contact owns a 2018 Toyota Sierra equipped with a Joysceer USA Inc, Hand Control Unit. The contact stated that while operating the vehicle, the message advising to "Stop immediately" was displayed with the error code: 4209 BSM. The contact stated that later a second error code: 1069 SAM was displayed. The contact stated that the messages were due to a malfunction of the Hand Control Unit. The cause of the failures was not yet determined. The manufacturer and installation facility were contacted regarding the failure, but no response was provided. No identifying information was available for the equipment. The failure mileage was 2,000.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Suspension
Reports naming suspension components — springs, struts, shocks, control arms and related hardware.
From owner reports, verbatim
THE VEHICLE HAS BEEN WEARING TIRES DOWN UNEVENLY TO THE POINT STEEL BRAID BECOMES EXPOSED. IT HAS HAD 3 SETS OF TIRES IN LESS THAN 2 YEARS. IT HAS BEEN ALIGNED TWICE. THE REAR WHEELS ARE NOT WITHIN SPECS AND ARE FIXED AND IN ADJUSTABLE. TOYOTA HAS REFUSED TO LOOK INTO THE PROBLEM ANY FURTHER AND HAS STATED THAT IT MIGHT BE HOW THE VAN RIDES. HAVING THE ALIGNMENT OFF CAUSES THE TIRES TO WEAR DOWN TO AN UNSAFE LEVEL AND IT AFFECTS VEHICLE HANDLING AND PERFORMANCE. *TR
Too few reports in this category for a page of its own — they appear in the full complaint list.
Tires & wheels
Reports naming tires, wheels, hubs, or the tire-pressure monitoring system.
From owner reports, verbatim
TL* THE CONTACT OWNS A 2018 TOYOTA SIENNA EQUIPPED WITH FOUR BRIDGESTONE TURANZA TIRES, SIZE: 235/55/18 (NA). THE CONTACT STATED THAT THE INSIDE SHOULDER OF EACH TIRE EXPERIENCED SEVERE WEAR. THE VEHICLE WAS TAKEN TO MY AUTO IMPORTS TOYOTA (1860 EAST STERNBURG RD, MUSKEGON, MI), BUT THE CAUSE OF THE FAILURE COULD NOT BE DETERMINED. THE TIRE MANUFACTURER WAS NOT NOTIFIED. THE TIRE AND VEHICLE FAILURE MILEAGE WAS 30,000.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Exterior lighting
Reports naming headlights, tail lights, turn signals and other exterior lighting.
From owner reports, verbatim
I RENTED A 2018 TOYOTA SIENNA ON A RECENT TRIP TO HAWAII. UNLIKE EARLIER SIENNA MODELS (WHICH HAD BOLDER, THICKER LABELS FOR THE INDICATORS), THE INSTRUMENT PANEL WAS VERY FAINT AND HARD TO READ IN DAYLIGHT. IN SHADE, IT WAS ALMOST INVISIBLE. I CHECKED THE MANUAL TO SEE IF I COULD TURN THE BRIGHTNESS UP, BUT IT APPEARS TO HAVE BEEN DESIGNED THIS WAY. I'M CONCERNED THAT NOT BEING ABLE TO SEE THE INSTRUMENT PANEL TO OBSERVE SPEED OR OTHER INFORMATION COULD CAUSE AN ACCIDENT, ESPECIALLY IF YOU HAVE TO TAKE YOUR EYES OFF THE ROAD BECAUSE IT'S SO HARD TO READ. IT'S ENOUGH TO MAKE ME NOT BUY THIS CAR, BECAUSE IT MADE ME FEEL VERY UNSAFE IN DRIVING.
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 .