559 of the
10,828 complaints filed about the Toyota Sienna
are about the transmission —
5% of everything owners reported.
The worst model year for it is 2004.
559
Complaints
5%
Share of all complaints
43
Crashes
3
Fires
Transmission & Drivetrain complaints by model year
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)
NHTSA complaint #11750202 — an unverified report by a vehicle owner.
I, as well as other owners of 2017–2018 Toyota Highlanders and 2017–2018 Siennas are experiencing serious transmission issues—including high-pitched whining, erratic shifting, clunks, hesitation, and premature failure. My 2017 Toyota Sienna has the UA80 8-speed automatic transmission at issue and started whining upon acceleration in March/April 2026 timeframe. It has always had the clunking and hesitation problem. According to Gears Magazine, the issue stems from a flawed assembly process involving the counter drive gear support. A locking tab meant to secure a vital retaining nut was not bent properly during factory assembly. This leads to gear movement, internal wear, whining, and eventually failure. Unknown to me, in 2019, Toyota had acknowledged the problem in Technical Service Bulletins T-SB-0160-18, T-SB-0008-21, which only go to dealers, and implemented a limited Customer Support Program (CSP ZJC)—but only offered coverage to a narrow group of VINs, not to all VINs for model years that have these transmissions. My car is experiencing these same symptoms. My Toyota Dealer confirmed this problem and recommended a transmission replacement for $11,000 including labor. They said my VIN was not included in the Customer Support Program. Driving with a failing transmission is highly dangerous. A bad transmission can cause sudden power loss causing the car to halt to a sudden stop, unintended acceleration, or my car might get stuck in neutral while driving. I could lose control or be unable to get to the shoulder on the highway, cause a rear-end collision, or get stuck in busy traffic. DESIRED OUTCOME REQUEST: My VIN should be covered under the Customer Support Program in the category of cars that are “less than 10 years old regardless of mileage” or a full recall of all VINs of these model years with these transmissions should be executed. Thank you.
NHTSA complaint #11749682 — an unverified report by a vehicle owner.
The contact owns a 2007 Toyota Sienna. While the contact’s wife was pulling into the parking space, the transmission shifter was shifted into park(P), and the vehicle suddenly rolled forward approximately four feet. The parking brake was activated, preventing the vehicle from crashing into a parked vehicle. The vehicle was towed to the residence. While examining the vehicle, the contact determined that the shifter cable bushing had failed and needed to be replaced. The vehicle was not yet repaired. The manufacturer and local dealer were notified of the failure. Additionally, previously while driving there was smoke coming from the engine compartment and the vehicle stalled. The vehicle was towed to the local mechanic who diagnosed the vehicle and determined that the oil cooler line had failed causing engine oil to spill from the engine. The rubber oil cooler line was replaced with an updated improved oil cooler line, and the vehicle was repaired. The failure mileage was 170,000.
NHTSA complaint #11746381 — an unverified report by a vehicle owner.
I have a 2017 Toyota Sienna XLE with about 120k miles on it. Out of nowhere the transmission was gear hunting and surging. It eventually became impossible to get it above 30 mph. It seemed like the transmission just went haywire. No lights on the dash let me know anything was wrong. Thankfully I had just pulled off the highway. Otherwise it could've been bad. I couldn't drive it safely so I had it towed to the nearest Toyota dealership. They said that the transmission needed to be replaced. $9k....
NHTSA complaint #11746069 — an unverified report by a vehicle owner.
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!
NHTSA complaint #11745443 — an unverified report by a vehicle owner.
We experienced a high whine for a couple of months. No codes were being read by any mechanics. Then the transmission started slipping between 2nd and 3rd gears, and then we couldn’t reverse. Now it’s not switching gears at all. There is a recall for our year and type of transmission, for this issue, but our vin number is not included in that recall.
NHTSA complaint #11742281 — an unverified report by a vehicle owner.
I have a 2017 Sienna AWD with a UA80 Transmission and the Check AWD System light appeared. I was able to drive it to Towne Toyota in Ledgewood, NJ and they detected the Sienna having DTC Codes P07407E, P27137F and P27567F. They they recommended a transmission replacement costing $9260.84 before tax that I can't afford right now. I am still able to drive the Sienna but Towne Toyota said that the Transmission will eventually fail. After some research, I discovered there is "ZJC UA80 Warranty_Enhancement" by Toyota. I am troubled that the service folks in Towne Toyota did not make me aware of this program! I am afraid to drive the vehicle knowing that the Check Engine Light may reappear. Or worse, the transmission can completely fail unexpectedly that may prevent me or other vehicles from avoiding a collision. It could also strand me on a busy highway and can possibly put my family at risk.
NHTSA complaint #11739882 — an unverified report by a vehicle owner.
The transmission went out. It wouldn't shift going 45-55 mph. We stopped at a light and put it into Park, then put it into drive but it wouldn't go. We were stuck at a light in traffic 10:30pm. We had to call 911 to get a cop to sit behind us so we wouldn't get hit. My wife, my 3 kids, and I were in the minivan. While waiting for the tow truck I saw on reddit that many 2017/2018 Toyota Sienna's had transmission problems. The vehicle is at Milton Martin toyota in Gainesville, GA. Toyota says it isn't covered by Bulletin ZJC. Toyota said the transmission is the issue.
NHTSA complaint #11739526 — an unverified report by a vehicle owner.
Transmission is making a winning sound. Toyota had issued a Customer Support Program (Program ZJC/POL19-04) for some of that year but it seems to affect more than what they have allowed
NHTSA complaint #11738660 — an unverified report by a vehicle owner.
I am writing to report a safety defect regarding the 8-speed automatic transmission in my 2017 Toyota Sienna. The vehicle exhibits severe hesitation during acceleration, harsh shifting, and a high-pitched whining noise, specifically consistent with the 'whine of death' described in Toyota's Customer Support Program ZJC and related Technical Service Bulletin T-SB-0160-18.Despite these identical symptoms, my vehicle’s VIN is not included in the coverage list. This hesitation during acceleration creates a serious safety issue, as the car fails to accelerate unexpectedly when attempting to merge or cross traffic. My vehicle is equipped with the UA80F/E transmission, which is documented to have a faulty assembly (improperly bent washer tab). I request that NHTSA investigate the exclusion of my VIN from this program, as the defect poses a significant risk to passenger safety and the safety of others on the road.
NHTSA complaint #11737861 — an unverified report by a vehicle owner.
My Toyota sienna is a 2020, has 83,000 miles and has recently been squealing when I accelerate. I took the van to a local body shop and they said it seems to be my transmission. I called Toyota immediately and they knew that the transmissions were faulty and that they would try to work with Toyota to get it fixed. There is no way I can pay 9k for a new transmissions because they put in faulty ones.
NHTSA complaint #11736554 — an unverified report by a vehicle owner.
The vehicle is a 2020 Toyota Sienna. While driving, the engine suddenly shut off without warning, creating a dangerous situation and loss of power. This occurred while transporting children, increasing the safety risk. A mechanic inspected the vehicle and diagnosed a failure of the low-pressure fuel pump. The problem appears intermittently — sometimes the vehicle runs normally, and other times it stalls or loses power. The check engine light has turned on and off. This issue matches the known defect related to the Denso fuel pump recall affecting many Toyota vehicles from similar model years. However, my VIN is not included in the recall. This is a serious safety concern because the engine can shut off unexpectedly while driving, which could lead to an accident. I believe this vehicle may have the same defective component as those included in the recall, even though it is not currently listed. The issue has been confirmed by an independent mechanic and the vehicle is available for inspection if needed.
NHTSA complaint #11733827 — an unverified report by a vehicle owner.
On April 15, 2026 Report filed with NHTSA from an accident-causing property damage due to a failure in the shifter mechanism while the vehicle was parked, ignition off, no keys in the vehicle and the brake pedal was NOT pressed. Manufacture initiated an investigation after we contacted their customer care line. Our vehicle was taken to a Toyota dealership on March 11, 2026. We received an email on April 13, 2026 stating Toyota's inspection did not identify any evidence that this incident was a result of a concern with the operation of our vehicles gear shift lever. We retrieved our vehicle from the dealership on April 20, 2026. On April 21, 2026 From our driveway the shift lever fell out of park into drive with the ignition off, no keys, and the brake pedal not pressed. Toyota claims no responsibility! How is this possible when they know there are active recalls for the same issue on earlier models? This is a massive public safety risk considering the vehicle can rollaway without the ignition even being on! I will continue to report this issue every time the shift lever falls out of park until resolved.
NHTSA complaint #11733159 — an unverified report by a vehicle owner.
On April 15, 2026 Report filed with NHTSA from an accident-causing property damage due to a failure in the shifter mechanism while the vehicle was parked, ignition off, no keys in the vehicle and the brake pedal was NOT pressed. Manufacture initiated an investigation after we contacted their customer care line. Our vehicle was taken to a Toyota dealership on March 11, 2026. We received an email on April 13, 2026 stating Toyota's inspection did not identify any evidence that this incident was a result of a concern with the operation of our vehicles gear shift lever. We retrieved our vehicle from the dealership on April 20, 2026. On April 21, 2026 From our driveway the shift lever fell out of park into drive with the ignition off, no keys, and the brake pedal not pressed. Toyota claims no responsibility! How is this possible when they know there are active recalls for the same issue on earlier models? This is a massive public safety risk considering the vehicle can rollaway without the ignition even being on! I will continue to report this issue every time the Shift lever falls out of park until resolved.
NHTSA complaint #11733164 — an unverified report by a vehicle owner.
On April 15, 2026 Report filed with NHTSA from an accident-causing property damage due to a failure in the shifter mechanism while the vehicle was parked, ignition off, no keys in the vehicle and the brake pedal was NOT pressed. Manufacture initiated an investigation after we contacted their customer care line. Our vehicle was taken to a Toyota dealership on March 11, 2026. We received an email on April 13, 2026 stating Toyota's inspection did not identify any evidence that this incident was a result of a concern with the operation of our vehicles gear shift lever. We retrieved our vehicle from the dealership on April 20, 2026. On April 21, 2026 From our driveway the shift lever fell out of park into drive with the ignition off, no keys, and the brake pedal not pressed. Toyota claims no responsibility! How is this possible when they know there are active recalls for the same issue on earlier models? This is a massive public safety risk considering the vehicle can rollaway without the ignition even being on! I will continue to report this issue every time the Shift lever falls out of park until resolved.
NHTSA complaint #11733165 — an unverified report by a vehicle owner.
On April 15, 2026 Report filed with NHTSA from an accident-causing property damage due to a failure in the shifter mechanism while the vehicle was parked, ignition off, no keys in the vehicle and the brake pedal was NOT pressed. Manufacture initiated an investigation after we contacted their customer care line. Our vehicle was taken to a Toyota dealership on March 11, 2026. We received an email on April 13, 2026 stating Toyota's inspection did not identify any evidence that this incident was a result of a concern with the operation of our vehicles gear shift lever. We retrieved our vehicle from the dealership on April 20, 2026. On April 21, 2026 From our driveway the shift lever fell out of park into drive with the ignition off, no keys, and the brake pedal not pressed. Toyota claims no responsibility! How is this possible when they know there are active recalls for the same issue on earlier models? This is a massive public safety risk considering the vehicle can rollaway without the ignition even being on! I will continue to report this issue every time the Shift lever falls out of park until resolved.
NHTSA complaint #11733166 — an unverified report by a vehicle owner.
Loss of power highway speeds, jerky shifting, “sealed” transmission leaking fluid. Check engine light and service required light. I have noticed poor performance with this vehicle before and reported it to the dealer to no avail. Toyota has enacted “customer support program ZJC” but the dealership will not honor.
NHTSA complaint #11731925 — an unverified report by a vehicle owner.
My transmission has started with a whining noise, Toyota knows about this issue with thousands of cases regarding the faulty transmission, yet only a few are being covered under a customer support bulletin ZJC. We need to hold Toyota responsible for this issue. We were just told today they won't help us at all. Yet now we are left with a van that we can't use and if we decide to fix it for 10k they are saying the transmission is backordered for months We had to pay Toyota $180 to diagnosis what we already knew was wrong with the vehicle so they would even consider if they would cover it.
NHTSA complaint #11731611 — an unverified report by a vehicle owner.
2019 Sienna XLE with 77,000 miles has a UA80 Transmission is whining at the final gear per Imperial Toyota Milford MA service center. They want to replace the transmission for 9,000 USD and Toyota Corporate refuses assistance. It appear to be a common defect which could lead to transmission lockup if the gear fails.
NHTSA complaint #11731560 — an unverified report by a vehicle owner.
The contact owns a 2015 Toyota Sienna. The contact stated that while the vehicle was parked, and the shifter lever was turned off, it unexpectedly fell down, causing the vehicle to shift into drive and roll down the street, where it crashed into a house. At the time of the incident, the vehicle was occupied by one three-year-old and two six-year-old children. One of the six-year-old occupants attempted to move the shifter into park while another attempted to steer the vehicle. The passenger-side sliding door was ajar. There were no warning lights illuminated. There were no reported injuries, fire, or airbag deployment. A police report was filed. The vehicle was taken to a local dealer; however, the failure was not diagnosed or repaired. The manufacturer was contacted, but declined the claim. The failure mileage was approximately 119,274.
NHTSA complaint #11731336 — an unverified report by a vehicle owner.