general problems of the 2021 Toyota Highlander - part 1

Transmission. My 2021 Toyota Highlander with approximately 94,500 miles developed a consistent whining noise during acceleration. The issue occurs daily during normal driving and appears to be worsening. A Toyota dealership diagnosed the problem and confirmed the noise is coming from the transmission and that the transmission requires replacement. This appears to be a premature failure of a major drivetrain component. The condition could lead to loss of power or transmission failure while driving, creating a potential safety risk. There was no prior warning, and the vehicle has been properly maintained.

Car makes a high pitched whining noise at low speeds of approx. 10-30 mph.

2021 Toyota highalnder ua80f transmission whine / known defect - potential for sudden failure I own a 2021 Toyota Highlander platinum v6 awd (ua80f 8-speed automatic transmisstion) purchased in July 2021. Current milage is 78k. Starting 3 days ago I noticed a faint whine noise coming from the transmission. The pitch changes with speed and when the throttle is depressed (it's louder under load/acceleration). This matches the exact symptoms described in Toyota TSB t-sb-0008-21 for whine/grind noise caused by the front carrier assembly pinion shaft issues in 2021 Highlanders with ua80 transmissions. On April 27, I went to a Toyota dealer to confirm the source of the noise and diagnose. As per their diagnosis report "tech took vehicle on road test to duplicate concern, after confirming complaint vehicle was then lifted up and inspected while under a load, tech as able to isolate noise to transmission at this time, fluid level and condition was inspected to ensure there were no signs of shavings or discoloration and after inspection tech found nothing abnormal during fluid level check. Tech then ran a health check to ensure there were no dtc present related to transmission concern and found no dtc present. Recommend replacing transmission and torque converter at this time". They provided a quote of $9,392. This condition represents a safety concern because the internal wear can progress to harsher shifting, loss of power, limp mode, or complete transmission failure while driving, potentially causing a crash or stranding the vehicle in traffic. I have audio/vehicle recordings of the whine and service records showing regular Toyota dealer maintenance. I am requesting the the NHTSA investigate this ongoing ua80 transmission issue as it appears to be a known manufacturing or design defect tat continues beyond the narrow TSB applicability and warranty limits.

My automatic transmission failed per the dealership and is just outside of the warranty but is considered a premature failure based on the expected life of the vehicle.

My 2021 Toyota Highlander equipped with the ua80 transmission developed a whining/grinding noise under acceleration around 73,000 miles. Toyota diagnosed internal transmission failure and recommended full replacement costing approximately $9,000. Toyota issued TSB t-sb-0008-21 acknowledging defects involving the front carrier assembly pinion shafts in these transmissions. This defect creates a potential safety hazard due to possible loss of power or drivability during highway operation. I am requesting that NHTSA investigate the widespread transmission failures affecting 2021 Highlanders and related Toyota vehicles.

A whining noise was observed at around 78k miles. Brought to the dealer and they indicated parts in the transmission are failing and it requires replacement. They said this has been happening more frequently on 2021 Highlanders (also see t-sb-0008-21). It's also a well-documented issue online. My contact with Toyota was that they did not intend to cover any repairs as the vehicle is out of warranty, even though it's not an isolated issue. They would not disclose how many vehicles have reported this issue. I believe it has reached safety recall-level.

Transmission has failed as have many others of the same year make and model without acknowledgement of a manufacturer defect.

My 2021 Toyota Highlander was my first car I purchased that I saved up for and has had a sudden issue accrue with a winning sound out of now where. I took it to the dealer ship and they told me I need a new transmission. My vechile only has 73k miles and I noticed this sound is getting worst and worst. I don’t know what to do so I turned to the internet and I was blow away to see how many people have this same issue with the same year and it’s been happing to so many people. I am a father of a special needs child and I sport my family on my own I can not afford to replace this and they won’t do anything for me. I beg anyone that reads this to please help us out cause this is not fair they we pay our hard earned money to get hit with this unexpected issues that they obviously know about but want do anything cause it will ruin there rep.

Transmission failure @110,000miles and a $9000. 00 replacement cost. Service advisor at Toyota dealership indicated they have seen other similar failures on this Highlander platinum model at their dealership but unit is out of warranty by a few thousand miles.

Car was making whining sound with acceleration at 62k miles. Dealer told me I need to spend 8k on a replacement.

During acceleration above 25 mph a noticeable whining sound is heard from the transmission. When not acceleration the sound goes away. The vehicle only has 72300 miles.

The transmission began making a wheezing sound. The dealership looked at the vehicle and determined it needed a new transmission. This is a known problem. Toyota issued a service bulletin on the issue in February 2021. I purchased the vehicle a few months after that. T-sb-0008-21.

60k miles on the car and the transmission needs to be replaced out of pocket due to a gear pinon wearing down. This is a 10k dollar repair and just happens to be after the warranty has expired.

The contact owns a 2021 Toyota Highlander. The contact stated that while driving at an undisclosed speed, there was a whining sound coming from the vehicle. There was no warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed with transmission failure. The dealer stated that the transmission needed to be replaced. The vehicle was repaired. After the vehicle was parked and turned off, there was transmission fluid leaking from the vehicle. There was no warning light illuminated. The vehicle was taken back to the dealer, where it was diagnosed and determined that the head gasket had failed and needed to be replaced. The vehicle was repaired. The contact then noticed fluid leaking from the transfer case while the vehicle was parked and turned off. The vehicle was taken back to the dealer, where it was diagnosed and determined that the transfer case had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 74,700.

My vehicle is experiencing a transmission safety issue that has been diagnosed by the authorized Toyota dealer service center (Toyota of scranton). During my most recent service visit on 3/2/26, the dealer reported that the transmission is “failing and whining” and recommended full transmission replacement. This condition creates unsafe driving behavior, including abnormal whining noise during acceleration and the concern for sudden transmission failure while driving. The Highlander started exhibiting issues with the transmission within the past 7 days. This issue appears consistent with the known transmission defect referenced in Toyota technical service bulletin t?sb?0008?21, which addresses whining and grinding noises caused by internal transmission component failure in 2021 model?year vehicles equipped with ua80-series transmissions. Multiple independent reports indicate that this condition can worsen and may lead to loss of power or drivability while the vehicle is in motion. For safety reasons, I am submitting this complaint so the issue can be evaluated as part of any ongoing or future defect investigations. I am concerned about the potential risk of transmission failure while driving, which could increase the chance of a crash.

The contact owns a 2021 Toyota Highlander. The contact stated that the vehicle experienced transmission failure while driving. There was an abnormal whining sound coming from the vehicle while accelerating, and the sound increased in volume while driving. There was no warning light illuminated. The vehicle was taken to the local dealer, where it was diagnosed with an internal transmission failure. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 55,803.

The contact owns a 2021 Toyota Highlander. The contact stated that while driving at an undisclosed speed, there was an abnormal whining sound coming from the transmission. The contact was concerned about the sound and contacted a dealer. The vehicle was driven to the dealer and was diagnosed with transmission failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 60,347.

I am reaching out regarding our 2021 Toyota Highlander which currently has $65 k miles and is just out of warranty. Recently we noticed a wining noise during acceleration. We took the vehicle to the dealer who told us that the transmission will need to be replaced. $9500 repair. This is a known issue with Toyota and they will not work with us on this. We are stuck! no customer goodwill! thank you!.

I purchased my brand new Highlander on January 31, 2021 and was told today that I need a transmission replacement. My vehicle started about two month ago with a whining sound while accelerating. My vehicle currently has 78,000 miles and is out of the extended warranty of 60,000/5 year. I learned that Toyota released a bulletin on February 9, 2021 stating transmission issues for particular Toyota models, the Highlander being one. After researching the issue, there are several stories of Highlander owners who are experiencing the same issue. It’s a shame that they knew of the problem in February 2021 and with the transmission replacements on vehicles less than 5 years old and haven’t issued a formal recall for this known defect.

The vehicle experienced a transmission failure at approximately 62,000 miles, which required a transmission replacement. Toyota replaced the transmission with a rebuilt transmission. Immediately after the repair, the vehicle began experiencing multiple issues that were not present prior to the repair. The vehicle initially would not reverse, and the battery was drained shortly after the repair was completed. Following the repair, the vehicle has continued to experience ongoing electrical malfunctions, including dashboard warning lights, system alerts, and dash lights flashing during remote start. The vehicle has also developed a rattling noise underneath the vehicle. The exact failed component has not been clearly identified. The dealership has provided changing diagnoses and has not provided written diagnostic documentation despite requests. The vehicle has been inspected by the dealership multiple times; however, the issues have not been resolved. During a recent diagnostic, the dealership stated that the catalytic converter is now the issue, but this does not address the ongoing electrical problems. These issues raise safety concerns due to unpredictable vehicle behavior and potential failure of critical systems while driving. Warning lights and system errors began appearing after the transmission repair and have continued since that time. The vehicle is available for inspection upon request.

Toyota is asking me to pay for a brand new transmission replacement in my car that is only 5 years old, 74,000 miles on it. The cost is $10,000. How is it possible a brand new vehicle is needing this? I have read a lot of reviews that Toyota is knowingly using the transmission type that they even had to recall on earlier models. Why are they still making vehicles using this type of transmission when it continues to need total transmission replacement so early on? and offer zero assistance. We bought Toyota because we thought it was the best. I will never buy Toyota again, this is a huge cost for a young family with a teachers salary.

Transmission has started to whine, my understanding is this is common for the transmission I have. I have had this verified by 2 different garages. There are no engine lights showing. The noise started around 90k.

I had the 60,000 mile service on February 2,2026 and after the service was completed I left the dealership and got on the freeway to go home. I heard a whining noise and immediately turned around and took it back to the dealer. I took the mechanic who worked on my car for a drive and he was able to hear the winding noise and we returned to the dealership. It took the mechanic three hours to come to the conclusion that I needed a new transmission. They still have my car and I have not heard anything about coverage or when it will be done.

The contact owns a 2021 Toyota Highlander. The contact stated that there was an abnormal winding sound coming from the vehicle while accelerating. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed with transmission failure. The vehicle was not repaired. The contact called a transmission shop and was informed that the part to repair the vehicle was on back order. The manufacturer was contacted, opened a case, and referred to the NHTSA hotline to report the failure. The failure mileage was approximately 106,000.

Known transmission failure. Whining noise when accelerating. T-sb-0008-21.

The transmission in my 2021 Toyota Highlander began making a loud whining/whirring noise that increases with vehicle speed. The vehicle was inspected by a Toyota dealership, and I was told the transmission has failed and needs to be replaced. Toyota stated the repair would be out of pocket, despite the vehicle’s age and proper maintenance. There were no warning lights prior to the failure. This condition affects drivability and raises safety concerns, including the risk of sudden transmission failure or loss of power while driving, especially at highway speeds. I believe this is a premature transmission defect and am reporting it for investigation.

Whinning noise during acceleration on the road and gear shift problems.

- the vehicle has been experiencing shifting issues (its an automatic vehicle) when driving in all instances and at all speeds that has progressively gotten worse over the past 4-8 weeks. - as it seems to be a transmission issue (and a known one pending litigation) the safety issue is if the transmission fails during operation of the car. - it was brought to a dealership to be inspected after it was initially felt as more of a vibration than the more harsh shifting/engine sounds and issues that it is currently experiencing. The dealership thought it to be the front hub assembly/bearing that was the issue. I had the front driver side replaced and the issue still remains and has continued to worsen. It has not been inspected by the manufacturer, police, or insurance representative. - there have been no warning lamps or messages at all. - through research it appears this is a known issue with ongoing litigation (2 class action lawsuits currently in litigation related to ua80f transmissions of which it appears that our VIN is in the affected group).

We began noticing a whining sound that has progressively gotten louder and more frequent upon acceleration. After taking it to the dealership, they claim it requires a transmission replacement. According to the dealership themselves and information online, this seems to be a common defect with 2021 Highlanders.

Technical service bulletin was issued for my 2021 Highlander car in February of 2021 for a well documented transmission issue (whine and grind noise). We are now put in a position that requires us to replace the transmission at a substantial cost. This expense is budget crushing and any assistance in getting Toyota to assist with the expense would be greatly appreciated.

The contact owns a 2021 Toyota Highlander. The contact stated that while driving at an undisclosed speed, the vehicle jerked abnormally and failed to accelerate as intended while depressing the accelerator pedal. The contact pulled to the side of the road. The vehicle failed, then failed to respond while in drive or reverse. No warning light was illuminated. The contact called for roadside assistance and had the vehicle towed to a safe location. The vehicle was then towed to an independent mechanic, who diagnosed the vehicle and informed the contact that the transmission had failed and needed to be replaced. The vehicle was not repaired due to the cost. The manufacturer was not notified of the failure. The failure mileage was unknown.

Transmission has failed, making high pitched whining noise while accelerating. Will need full replacement the car only has 66k miles on it - just out of warranty.

Transmission started to make a whining noise. After a month the sound increased in loudness and took to dealer to check. Came back with needing transmission replaced due to bad bearing. Was replaced with aftermarket warrenty protection.

I started hearing a winning noise that got louder with speed, this month I took it to the dealership in austin, TX and they said it needed a new transmission. It only has 67,219 miles. My 2008 was sold at 219k miles with no problems. I see online there has been problems with this type of transmission for many years. They are replacing it with the very same transmission. . . .

I was driving to a stop light when I heard a raddle. Pull over and all the oil came out the engine. When I took it to the dealer they told me that the engine blew up. 14k repair that Toyota would not cover the repair.