2017 Toyota Sienna: complete transmission failure

Filed Oct 31, 2026 · Transmission · AZ

I own a 2017 Toyota Sienna XLE Premium, FWD, 8-passenger,equipped with the UA80E automatic transmission. At approximately 150,000 miles, the transmission began making a whine in 3rd gear and higher, most noticeable under steady throttle and worse after the vehicle warms up. The sound appears to come from the transmission, but the exact failed component has not been confirmed. A drain and refill with Toyota ATF WS reduced the noise temporarily, but it returned after about 1,000 . The vehicle had approximately 156,000 miles when I last tracked the issue. I am concerned this may be an internal transmission bearing or other component failure. A transmission replacement or rebuild could cost thousands of dollars and Toyota has a ZJC but I’m told my vehicle isn’t covered although it fits the dates and requirements. I am reporting this issue to document the failure and ask the federal safety agency to investigate whether other 2017 Sienna vehicles equipped with the UA80E transmission experience similar whining or premature internal wear.

Filed Jul 11, 2026 · Transmission · CA

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.

Filed May 25, 2026 · Transmission · NJ

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.

Filed May 22, 2026 · Transmission · GA

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.

Filed Oct 21, 2025 · FL

While driving our vehicle on the highway, the check engine light suddenly came on and traction control turned off. Within moments, the vehicle began to stall and would not accelerate. My wife and children were in the car and we were nearly hit by another vehicle as she struggled to get the car to safety. It was a terrifying experience that put my entire family in danger, along with everyone else on the highway. Upon taking the car to the dealership, we were told the transmission failed and would need to be replaced.

Filed Jun 19, 2025 · Transmission · CO

We have started to experience the transmission whine at that is specified in Toyota's CSP ZJC documentation. We took our vehicle into our local Toyota Dealership Service Center and they confirmed that the whine was a transmission issue and that the only course of action to take would be to replace the transmission. Our vehicle was manufactured in the specified window (manufacture date 10/2016, manufacture data window from the program 7/2016-2/2018), it has the specified transmission model (UA80), we are within the coverage window stated in the support materials (within ten years of first use), we are experiencing the same transmission symptoms described in the program support materials (whining transmission noise), and we have been recommended by our local Toyota Service members to replace the transmission. From this information, it appears that we meet the criteria and are suffering the same issues as are referenced in the ZJC materials, but our VIN is not included in the program. I believe that is an error and the program should be expanded.

Filed Apr 28, 2025 · Transmission · MO

Transmission failure. The dealer confirmed the issue and was repaired at an independent shop. There are no warning lights and only audible sounds that caused us to have it checked out. This appears to be a more widespread problem as Toyota did issue a TSB for a subset of VINs of this model year.

Filed Feb 22, 2025 · Engine, Suspension · TX

Pressure Control Soleneoid "A" Prformance stuck oof -P0746. Second opionin: Valve bddy Assembly clutch kits inside transmission. Toyota of Dallas refuse to provide service. I had done Tranmission service done by them . Need to get it fix van with new transmission installed and correct any other recall of 2025 to be fix.

Filed Oct 15, 2024 · Transmission · MO

While trying to accelerate on an onramp to the highway, the transmission failed to enter into higher gear, and the check engine light came on. The 2017 Sienna currently sits at 112,951 miles. Leading up to this, we had noticed the van jolting when being put into drive or reverse, and acceleration was often sluggish, with a whirring sound. Inspection by the local Toyota dealership found that the entire transmission needed to be replaced. The serial number of the transmission starts with UA02, which wasn't part of any of the existing 2017 Sienna service bulletins.

Filed Sep 30, 2024 · Transmission · 110,000 miles · KS

The contact owns a 2017 Toyota Sienna. The contact stated while driving at an undisclosed speed, the contact became aware of a hard shift and a high-pitched whining sound while the transmission was shifting. The vehicle was taken to an independent mechanic where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure but provided no assistance. In addition, the contact was informed that the repair was not covered under recall. The failure mileage was approximately 110,000.

Filed Mar 25, 2024 · Transmission · UT

On Sunday, [XXX] (at 78,793 miles), our MY17 Sienna XLE AWD suddenly displayed a Malfunction Indicator Lamp (MIL) and a message advising "Check AWD System". The vehicle disabled its cruise control system and AWD system, and no longer displays the Eco indicator when traveling at constant speeds on flat terrain. There was no obvious change to vehicle shifting behavior; the shifting has always been sluggish and occasionally "hangs" at higher RPM before downshifting. There were no symptoms or MILs prior to this incident. We consider AWD to be a safety feature when driving with snow or rain, and we frequently traverse Box Elder Canyon where the summit is nearly 6K feet above sea level. We stopped by an auto parts store (O'Reilly) where they pulled codes from the OBD-II sensor. Their reader showed 3 codes: P2714, P0741, and P2757). The vehicle is currently at Young Toyota in Logan, UT. Young Toyota advised that while the vehicle codes are consistent with bulletin [XXX] , that it is not included by Toyota under their list of affected transmissions. The service agent said a solenoid that governs locking the torque converter was "stuck". Since it is outside the 60K miles/60 month powertrain warranty, Toyota is unwilling to provide goodwill towards a fix. The dealer recommended a "software fix", which may or may not solve the issue, and that a transmission replacement would follow. I am simply in shock that a vehicle we purchased new, have carefully maintained (including through Toyota's maintenance plan for 60K miles), could potentially have a failing transmission below 150K miles. This is the UA80F 8-speed automatic transmission, which I believe was first-equipped on the MY17 Sienna, replacing a reliable 6-speed A/T. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Mar 7, 2018 · Transmission · 10 miles · FL

Tl* the contact owns a 2017 toyota sienna. While depressing the accelerator pedal after a stop, there was a hard jerk and the rpms increased. There were no warning indicators illuminated. The contact stated that the failure was an ongoing issue with the vehicle ever since it was purchased. The miracle toyota (37048 us-27, haines city, fl 33844, (863) 956-1123) stated that the vehicle had transmission failure, which would disappear after driving the vehicle for awhile. While the contact's wife was driving the vehicle, a loud whining noise was heard. The contact's wife was able to turn off and restart the vehicle. After a few minutes, the noise disappeared. The contact researched the failure online and found a tsb issued by toyota for a software update. The vehicle was taken to miracle toyota (37048 us-27, haines city, fl 33844, (863) 956-1123) where it was diagnosed with needing the software updated for the ecu. The update was performed, but the failure persisted. The manufacturer was notified of the failure and a case was opened. The approximate failure mileage was 10.