2020 Toyota Highlander

My 2020 Toyota Highlander XLE AWD developed a high-pitched whining noise from the drivetrain/transmission area while accelerating. The noise increases under acceleration and stops when the accelerator is released. The noise is not present when the vehicle is in neutral. I brought the vehicle to an authorized Toyota dealership for diagnosis. The dealership confirmed the condition and determined that the transmission requires replacement. The vehicle had only recently exceeded 60,000 miles when the problem was diagnosed. My safety concern is that this appears to be an internal transmission failure occurring at relatively low mileage. Because the transmission is a major drivetrain component necessary to maintain propulsion, I am concerned that continued deterioration could result in loss of propulsion or a more serious transmission failure while the vehicle is being driven. Toyota has reviewed the dealership's diagnosis and has approved supplying a replacement transmission through goodwill assistance. The original transmission has not yet been removed and remains installed in the vehicle. I am reporting this condition because I have identified other complaints involving Toyota Highlanders with similar transmission whining under acceleration and subsequent transmission replacement. I am concerned that this may represent a recurring transmission defect rather than an isolated failure. Because the original transmission is still installed, the vehicle and transmission should currently be available for inspection by NHTSA or other appropriate parties if requested before the repair is performed.

The transmission started making a whining noise around 69,000 miles that a mechanic said was due to transmission failure. There were no warning lights or messages. I took it to the Toytota dealer who sold it to me new. They inspected it and confirmed that the transmission needed replaced which they did. Online research said these symptoms meant the transmission could fail at any time while driving it which could put passengers and others at risk.

The transmission had a catastrophic failure at 73,000 miles and six years after purchase. There has been a service bulletin issued with known defects on this transmission yet Toyota corporate failed to acknowledge that they installed faulty transmissions in the 2020 Toyota Highlander. The diagnosis was a failed pinion bearing which the dealer diagnosed to replace the transmission at nearly $10,000

We have a 2020 Toyota Highlander with 89K miles that we have owned since it was new. I was informed today to not drive it any long distances from the dealer due to an impending failure of the transmission, creating a large safety issue for me and my family. I understand there are related recalls of the UA80 transmission but none for this particular model; there are countless internet reports of failure. I implore the NHTSA to investigate and protect the motoring public.

The transmission can suddenly fail even at very early mileages. This is almost certainly related to T-SB-0008-21 that has defined a narrow number of transmissions though it appears to affect many more than outlined. This could cause sudden failure while operating the vehicle at any point in time and potentially lead to a crash without much if any warning. Toyota Brand Engagement is denying any assistance due to external service history from a prior owner rather than addressing the failed part outlined in the TSB. Failure reasoning cannot be provided from the dealership as Toyota does not allow the dealer technicians to open the transmission and instead mandate a full replacement.

I am submitting this complaint regarding a sudden and unexpected transmission failure in my 2020 Toyota Highlander. The vehicle experienced a major transmission malfunction without any prior warning signs, dashboard warning lights, diagnostic messages, or noticeable drivability issues. The failure occurred suddenly when the vehicle would no longer shift into reverse. When placed in reverse gear, the vehicle does not move. Additionally, when placed in drive, the transmission slips significantly, resulting in a loss of power and unsafe operation. The vehicle is no longer reliable or safe to operate on public roadways. At no time prior to the failure were there any illuminated warning indicators, check engine lights, transmission warnings, abnormal noises, or other symptoms that would have alerted me to an impending transmission problem. The lack of warning created a hazardous situation, as the vehicle's ability to accelerate and maneuver could be compromised without notice. The vehicle has been diagnosed as requiring major transmission repairs or replacement, with estimated repair costs approaching $7,000. Given the severity of the failure, the absence of any warning to the driver, and the significant financial burden associated with the repair, I believe this issue may represent a safety-related defect that warrants investigation. I am concerned that other owners of 2020 Toyota Highlanders may experience similar sudden transmission failures that could result in a loss of vehicle control, inability to maneuver safely, or exposure to hazardous traffic conditions. I respectfully request that NHTSA review this matter and determine whether a broader investigation into transmission failures affecting 2020 Toyota Highlander vehicles is warranted.