2018 Toyota Sienna problems and complaints
Owners have filed 71 complaints with NHTSA about the 2018 Toyota Sienna. The most-reported areas: Power Train (19), Unknown Or Other (13), Fuel/Propulsion System (9).
Key takeaways
- 71 owner complaints on file with NHTSA.
- 5 involve a crash, 0 a fire, 6 reported injuries.
- Complaints are unverified owner reports; recalls are confirmed defects.
| Component | Complaints | Share |
|---|---|---|
| Power Train | 19 | 27% |
| Unknown Or Other | 13 | 18% |
| Fuel/Propulsion System | 9 | 13% |
| Electrical System | 7 | 10% |
| Engine | 5 | 7% |
| Air Bags | 5 | 7% |
| Structure | 5 | 7% |
| Vehicle Speed Control | 5 | 7% |
| Seats | 4 | 6% |
| Fuel System | 4 | 6% |
| Gasoline | 4 | 6% |
| Service Brakes | 2 | 3% |
One complaint can name several components, so shares add up to more than 100%.
| Version | Overall | Front | Side | Rollover |
|---|---|---|---|---|
| 2018 Toyota Sienna VAN FWD | 5/5 | 4/5 | 5/5 | 4/5 |
| 2018 Toyota Sienna VAN AWD | 5/5 | 4/5 | 5/5 | 4/5 |
Latest complaints, as filed
Owner-written and unverified by NHTSA.
Power Train - filed 2026-09-17
Transmission whining above 20mph. Toyota customer care program [XXX] states my vehicle falls within timeframe but dealer and corporate will not honor repairs INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Electrical System - filed 2026-09-02
Odometer Fraud. The contact purchased a 2018 Toyota Sienna. It was discovered that there was a mileage discrepancy. The vehicle was a private sale. At the time of purchase, the mileage was 49,000. While attempting to resell the vehicle, the Auto Check report indicated that the mileage was 324,000.
Power Train - filed 2026-07-14
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...
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More for the 2018 Toyota Sienna
Complaints are reports filed by owners with the National Highway Traffic Safety Administration. NHTSA publishes them without verifying them, and counts rise with how many cars were sold, so compare years of the same model rather than different models. Crash ratings are NHTSA's own 5-Star Safety Ratings results.