2021 Toyota Highlander

My transmission started to have a noticeable whine at 53k miles. It became noticeably louder during acceleration. It was diagnosed at the Toyota dealership as a failing transmission. My vehicle was a few months out of warranty. I was told to contact Toyota corporate to ask for assistance. I was told since I did not have a service record at the dealership, they would deny my claim. I advised them the transmission was a sealed unit with no dipstick. My vehicle has been meticulously maintained with records. They said sorry, and the conversation ended.

Vehicle is experiencing a distinct, high-pitched mechanical whine or grind sound from the transmission during acceleration that increases in pitch with vehicle speed. The noise does not happen while cruising or coasting. This symptom aligns directly with Toyota Technical Service Bulletin T-SB-0008-21 ('Whine or Grind Noise From Transmission'). I am concerned about a premature, catastrophic internal bearing or gear assembly failure of the UA80 8-speed transmission while driving at highway speeds, which poses a severe sudden loss of propulsion safety risk.

This vehicle was purchased new in 2021 with 4 original miles. Today it has 58,000 miles and has been maintained, per manufacturer recommendations, a certified Toyota dealership. At around 56,000 miles we noticed a slight whine in first gear. This was attributed to normal noise that we simply had not noticed. by 58,000 miles the while had extended to all gears and become more prominent. Research online shows that this is a known issue with the UH80 transmissions and has been since at least 2017. Toyota has a TSB for it (TSB-0008-21). This was not mentioned at the time of purchase or any of the various maintenance appointments in the last 5 years. This KNOWN issue WILL lead to complete transmission failure. This can happen while parked or in motion and can include the transmission shifting out of an active gear, locking into a gear and being unable to shift to another or park/neutral and there is no way to avoid it. I called Toyota corporate about this because I was not made aware of the TSB until July of 2027 and was advised that, although I was below the 60,000 mile allowance, I had surpassed the 60 month coverage period by two months and would not be granted a warranty exception (Toyota case number: 260710000821). Due to a known defective part on a vehicle that Toyota sold without advisement of said known issue, I am expected to pay $8,000 in repair fee's for a 40,000 dollar car that I have already spent over $20,000 on. The dealership confirmed the issue on 7/28/2026 and are attempting to use my 3rd party warrant which only covers parts. I will still be expected to pay for the labor costs which they expect to land between 2-3k dollars. Toyota is knowingly allowing a defect to persist that puts their customers and anyone else on the road at the time, at risk of serious injury and death. They expect their customers to cover the cost of repairs for an issue that they were aware of at the time of sale

The contact owns a 2021 Toyota Highlander. The contact stated that while driving 25 MPH, there was an abnormal whining sound coming from the engine. The vehicle was taken to the dealer, where it was diagnosed with transmission failure due to a pinion shaft failure. The dealer determined that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 62,300.

The contact owns a 2021 Toyota Highlander. The contact stated that the vehicle was taken for oil filter maintenance and a spark plug change, and after the maintenance, the vehicle made an abnormal sound each time while accelerating. The dealer was contacted and diagnosed the vehicle with transmission failure. The vehicle was not yet repaired. The manufacturer was contacted and stated that the vehicle was out of warranty. The failure mileage was approximately 59,000.

I bought the vehicle used from a Cadillac dealer in Orlando with 72700 miles on it. At approximately 75000 miles my wife and I noticed a faint whine coming from somewhere. As it worsened, I researched the issue to find that Toyota has a TSB for a manufacturing defect in the transmission. As I understand it, the transmission can fail suddenly causing a serious safety concern. I need to fix this problem as soon as possible for my family’s safety but since I am out of the warrantee period and there are class action law suits in progress I am starting here. The cost of the repair, I am told will be $9000 a $11000. There should be a safety recall for this.

My 2021 Toyota Highlander Platinum is experiencing a transmission issue consistent with a known problem affecting the UA80 eight-speed transmission used in 2020–2024 Highlander models. The vehicle is currently at Greentree Toyota in [XXX] for diagnosis. This failure is occurring at 63,913 miles, only about 3,900 miles past the vehicle's 60,000-mile powertrain warranty. I have opened a case with Toyota (Case #XXX) and am requesting this be documented as part of a broader pattern reported by other 2020–2024 Highlander owners, including other 2021 Platinum trim owners INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Our Transmission is failing on our 2021 Highlander. It has a little over 76,000 miles on the vehicle. 2021 and 2022 seem to have many issues with the transmission failing. The dealership's estimate is almost $11,000! We only buy Toyotas and never had this issue with our Sequoia, sienna, avalon, Rav 4 with lots of miles and never needed a new transmission!