2020 Toyota Highlander

Shortly after the powertrain warranty expired, the automatic transmission in my 2020 Toyota Highlander began producing a loud whining/howling noise during normal driving. The noise appears to come from the transmission area and increases with vehicle speed. The issue was not present during the warranty period and began unexpectedly soon after expiration. The abnormal noise raises concerns about internal transmission failure and potential loss of drivability. This condition could pose a safety risk if the transmission were to fail while driving, especially at highway speeds or when merging into traffic. No warning lights or messages were displayed prior to or during the issue. The vehicle was inspected by a Toyota dealer, and the problem was confirmed to be related to the transmission.

The vehicle’s automatic transmission (power train) has developed a loud whining/whirring noise under acceleration. This noise increases with engine load and indicates internal mechanical failure. The transmission is still installed in the vehicle and is available for inspection upon request. This issue poses a safety risk because it causes hesitation and unpredictable acceleration behavior while merging or crossing traffic. There is also concern that the transmission could suddenly fail while driving, resulting in loss of propulsion and potentially causing an accident. The problem has been inspected and confirmed by a Toyota dealership, which advised that the entire transmission needs to be replaced at a cost of over $8,000, despite the vehicle having only approximately 77,000 miles. The vehicle has been inspected by a Toyota manufacturer service center. They identified the transmission failure but stated there are no current recall programs covering this specific VIN. No warning lights or error messages were displayed at any time before or during the failure. The first noticeable symptom was the transmission whining/whirring noise during acceleration, which began around 77,000 miles and continues to worsen.

Road noise was very loud. I thought it was a bearing and I took it to the shop and found out that the 'transfer box' on the side of the transmission had to be replaced. I was told that not replacing it could lead to major transmission failure. This cost $6000. Mechanic said it's unusual. Upon reading the internet I'm learning that I'm not the only one this and similar problems.

The car started making whining noises when pressing the gas pedal. Toyota reported "noise from transaxle final drive. recommend replace. vehicle ok to drive but noise will continue until transaxle is replaced." There are no warning lights, messages or other symptoms prior to the sound starting or currently. This is a known issue with its 8-speed automatic transmission (UA80E/UA80F) that can cause whining, erratic shifting, and premature failure. This issue is the subject of a Customer Support Program (CSP ZJC) and several lawsuits, but the program has limited coverage for VINs, leading to owner complaints about a lack of assistance from Toyota.