2021 Toyota Highlander power train problems

Sep 21, 2026 · failed Sep 18, 2026 · PA

In my Toyota Highlander 2021 XLE model ,on 9/18 I hear a whinning noise when gas pedals is pressed. Took it to the Toyota TriCounty dealer in Limrick,PA for diagnosis. It was reported it is due to a transmission issue and it would cost around 10,600$ to repair. I haave been taking this vechile to same dealer to servie for last 5 years and this problem did not surface. I was told the car can be driven but would the car would stop when the transmission actually fails. Opened a case

Sep 14, 2026 · failed Aug 31, 2026 · 58,000 miles · IN

The contact owns a 2021 Toyota Highlander. The contact stated that while driving 22 MPH, there was an abnormal sound coming from the vehicle. The dealer was contacted by phone and made aware of the failure. The vehicle was taken to the dealer, where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The manufacturer was contacted by phone, and a case was filed. The contact was informed that the repair was not covered under recall. The failure mileage was approximately 58,000.

Sep 14, 2026 · failed Sep 14, 2026 · IN

Tech: SCOTT RICHART test drove vehicle performed inspection. Noise hear is coming from transmission internally. condition present is similar to condition described in T-SB-0008-21 for whine noise from transmission. Transmission would need replaced to remedy the noise. Vehicle is out of warranty, DOFU is 04/14/21. Transmission is not in the serial number range described in the TSB. Transmission serial # is A3A21C08858. QUOTED $8574.50 TO REPLACE TRANSMISSION WITH REMANUFACTURED TOYOTA TRANSMISSION.

Sep 14, 2026 · failed Sep 13, 2026 · WI

Transmission Failure Yes TSB No Warning Lights

Sep 11, 2026 · failed Sep 11, 2025 · TX

There is an unknown whine coming from the transmission when pressing on the throttle. It loud and high pitched.

Sep 10, 2026 · failed Aug 10, 2026 · WI

Leadcar Toyota LaCrosse WI has diagnosed and reported that the transmission needs to be replaced. Pertains to Service Bulletin T-SB-0008-21 the pinion shaft bearing defect. The major powertrain component is failing prematurely. Cost to repair is over $9,000 as it is out of warranty. We purchased the vehicle at 67,550 miles on 3/29/2025. Since we never owned a Toyota before we thought the whining of the transmission was unique to that vehicle. Once we heard about the service bulletin we took it in to get diagnosed.

Sep 9, 2026 · failed Sep 9, 2026 · IN

Transmission failure at 80,000 miles

Sep 9, 2026 · failed Aug 24, 2026 · IN

transmission has failed. Toyota states: Toyota Technical Service Bulletin T-SB-0008-21 addresses a whining or grinding noise in select 2021 Toyota vehicles equipped with UA80E orUA80F automatic transmissions caused by a defect in the front carrier assembly pinion shafts. Yes it can be available for inspection. This can be repaired with a $12,000 new transmission. * Sudden loss of acceleration: You may press the gas and the vehicle doesn’t accelerate normally. This is particularly dangerous when merging onto a highway, crossing an intersection, or passing. How this toyota highlander is putting safety at risk: * Unexpected shifting or jerking: A failing transmission can slam into gear, hesitate, or shift unpredictably, potentially causing loss of control. * Loss of drive: The transmission may suddenly stop transferring power to the wheels. You could be unable to move forward even though the engine is running. * Getting stuck in a gear: If it goes into a “limp” or failsafe mode, the vehicle may be restricted to a single gear and have very limited acceleration. * Loss of power while already moving: If the transmission disengages unexpectedly, you can lose the ability to accelerate out of a dangerous situation. * Difficulty maintaining speed: On a highway or uphill, a failing transmission may suddenly stop providing adequate power. * Transmission fluid leaks: A significant leak can cause the transmission to lose lubrication and worsen rapidly. Depending on where fluid goes, it can also create other mechanical problems. * Unexpected engine RPM increases: The engine can rev very high without the Highlander gaining speed (“slipping”), which can leave you unexpectedly slow in traffic. * Being stranded in traffic: A complete failure can leave the vehicle immobile, creating a collision hazard if you’re stopped in a travel lane or on a shoulder. unknown if it has been inspected by anyone. There is no warning lights. Then only way you know is by a high whining sound.

Sep 8, 2026 · failed Aug 14, 2026 · TX

The 8 speed automatic transmission (UA80E) in my 2021 Toyota Highlander Limited V6 FWD failed at 75,491 miles. The failure presented as a loud whining noise during acceleration between 30 and 40 mph. A Toyota dealership diagnosed complete transmission failure requiring full replacement of the transaxle assembly at a cost of $8,144.45 (repair order dated August 14, 2026). The dealership service manager confirmed in writing that the failure appears consistent with Toyota TSB T-SB-0008-21, issued February 9, 2021, which documented whine and grind failures of the front carrier assembly pinion shafts in this transmission family. My transmission was built in June 2021, after the serial range covered by that bulletin, and failed the same way, indicating the defect was not confined to the bulletin's production range. This transmission is the subject of multiple pending federal class action lawsuits alleging premature failure. A transmission failure of this type can result in sudden loss of power while driving, which is a safety hazard. The vehicle was purchased new from a Toyota dealership in July 2021, was maintained normally, and was never used under severe service conditions. The problem has been confirmed by the dealer. The vehicle and failed component are available for inspection and the vehicle remains at the dealership.

Sep 6, 2026 · failed Jul 1, 2026 · TX

**Component/System:** Automatic Transmission — 8-speed (UA80E/UA80F), Toyota Highlander **Description of the problem:** My 2021 Toyota Highlander (approximately 116,000 miles) has developed a high-pitched whining noise a while ago, that occurs during acceleration, consistent with the symptom described in Toyota's own Technical Service Bulletin T-SB-0008-21 (issued Feb 9, 2021) for whine/grind noise in the transmission on this model. The vehicle has not yet been formally diagnosed by a dealer or independent shop as of this filing; I am submitting this report proactively given the volume of documented failures in this transmission platform and to add to NHTSA's record before the condition potentially worsens. I am aware, through Toyota's own TSB and multiple pending class-action lawsuits (including Pallaya v. Toyota Motor Sales U.S.A., Case No. 2:25-cv-10613, C.D. Cal., and LeBoutheller v. Toyota, Case No. 4:25-cv-01389, E.D. Tex.), that this transmission (UA80E/UA80F, used in 2017-present Highlander and related Toyota/Lexus models) has a documented pattern of premature failure nationwide, often presenting first as this same whining noise, and in a number of owner-reported cases progressing to sudden power loss, shifting into neutral, or stalling — creating a serious safety risk to occupants and other drivers, particularly at highway speeds.

Sep 3, 2026 · failed Aug 19, 2026 · GA

At 57,000 miles the dealership says the transmission must be replaced. Toyota refused to replace it under warranty because they stated it wasn't serviced at Toyota consistently. There isnt a service for the transmission under 100k miles. This is a known issue with this transmission and they act oblivious to this issue.

Sep 2, 2026 · failed May 30, 2026 · OH

The transmission whining started 70,000 miles and it is progressively gotten worse, there has been some sudden shifting at times. The manufacturer has known about this 8 speed transmission. Problem since 2017 and they haven’t done anything to improve it. Isn’t is something that the warranty only covers the drivetrain and. Transmission till 60,000. And know they are telling us that we have to pay anywhere from $7,000-$12,000 to,have it replaced. We have taken it to the Toyota dealership Thayer Toyota in bowling green,oh and they checked it out. And said that the front part of the transmission is ok it’s but the rear differential is the one that is going bad. We are hoping that there will an investigation on this UA80 transmission to see how many of the toyota models that have this transmission in it, have been reported and if any after the 60,000mile they have covered to be repaired at there cost. We understand that there is a CLASS ACTION LAWSUIT against this transmission. We would appreciate any help that you can get us. We can be contacted at [XXX] or phone number [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Sep 2, 2026 · failed Aug 19, 2026 · NJ

1. The car makes a squeaky sound when I accelerate. The faster I go the louder the noise becomes. I took the car to the Toyota dealership and was told that the transmission needs to be replaced. The car is only 5 years old. I checked online and noticed a lot of other people are also complaining about the same issue with their 2021 Toyota Highlander. 2. While driving on the Turnpike a few months ago, the driver side front door suddenly popped open on me. I had to hold it with my left hand, switched lane to pull safely to the shoulder lane in order to close it. The door was completely closed prior to this incident. When that happened, I was already driving on the road for over 1 hour. There was no previous signal that it was opened. It just popped open out of nowhere.

Aug 31, 2026 · failed Aug 14, 2026 · NJ

Toyota has known that the UA80 transmissions are faulty & they have not issued a recall. Mine failed at 60,500 miles just outside of the warranty period. I paid over $5,000 to have it replaced & the dealer confirmed that it required replacement due to a faulty transmission assembly. Toyota refuses to issue a recall or cover full costs for replacement.

Aug 27, 2026 · failed Aug 27, 2026 · IL

It's about the problem with the automatic transmission UA80 already has the buzz That many customers are complaining sometimes it has jerks too.

Aug 27, 2026 · failed Aug 1, 2026 · CA

The car's transmission is failing. •The "Whine of Death": The most common early warning sign is a high-pitched, airplane-like whining noise that rises in pitch with vehicle speed/engine RPM, especially once the transmission reaches operating temperature. •Technical Service Bulletins (TSBs): Toyota has issued internal bulletins (such as T-SB-0008-21 and related updates) addressing abnormal transmission noises and replacement protocols for affected V6 models. •No Formal Safety Recall (as of mid-2026): While the issue has spurred class-action lawsuits and high NHTSA complaint volumes, there has not been a mandatory safety recall for widespread replacement, leaving post-warranty owners to rely on goodwill assistance or third-party warranties.

Aug 26, 2026 · failed Aug 3, 2026 · SD

At 66,000 miles the transmission on my 2021 toyota highlander is failing. This is a known issue with these transmissions and toyota is actively working against people to help get the parts replaced at their cost.

Aug 21, 2026 · failed Jun 1, 2026 · GA

I made my last payment on my Toyota in June and the week I made my payment my mechanic confirmed a whining that had just started to be a transmission failure. After taking to another specialty transmission shop my transmission is failing. The internal bearings are failing just like the recall in other 2021 models. I’ve been told my VIN isn’t part of the recall but it is the same problem. I am having to pay $8500 on a transmission for a just paid off Toyota. I was so excited to be debt free. This is unacceptable. A Toyota transmission should not fail the minute it’s paid off. I’m very disappointed in Toyota. I contacted the dealership and the warranty help team to try to get part or all paid for and got nowhere. My car needs to be included in the recall of Highlanders with the internal bearing failure.

Aug 21, 2026 · failed Aug 20, 2026 · UT

Bought my 2021 Toyota Highlander XLE AWD 3 years ago due to supposed safety and reliability. Transmission went out right after warranty at 64,000 miles. Was not made aware that this is a common issue. Vehicle hard shifted and suddenly lost power when driving home with my 4 year old while making a left turn, and we were almost hit by oncoming traffic. Have not had prior issues in the past to suspect this would happen, so it was very sudden and unexpected. There has been no recalls or awareness for this which could have seriously injured my child and I. Went to take it to the closest mechanic right away to troubleshoot since the vehicle was not throwing any codes.

Aug 19, 2026 · failed Jul 8, 2026 · MD

This vehicle experienced transmission failure at 43,000 miles. There is a technical bulletin regarding a known manufacturer defect for this Make/Model/Year (TSB-008-21) and we were told by our Toyota service technician that our vehicle displayed all of the same symptoms as those identified in the technical bulletin. Unfortunately the serial number for our vehicle was not included in the bulletin and we were four months outside of the power train warranty, therefore Toyota refused to cover the costs of replacing the transmission. We are requesting that TSB-008-21 is reviewed and expanded to cover additional vehicles including ours that were affected by this manufacturer defect that caused both a safety risk as well as a financial hardship for our family.

Aug 19, 2026 · failed Jul 1, 2026 · WI

At around 75000 miles (less than 5 year old vehicle) the transmission exhibited a noticeable whine. After further research I presented the vehicle to the local Toyota dealer service department. An active technical service bulletin T-SB-0008-21 that describes a manufacturing defect with the front carrier assembly pinion shaft (essentially a catastrophic transmission failure) was matched to the symptom the vehicle was exhibiting. Further, my transmission serial number is directly within the affected production defect list. Failure to replace this transmission at significant cost (should not normally be routine maintenance on a highway driven vehicle at this age and mileage) could result in total loss of power and control causing the potential for a severe traffic hazard or accident.

Aug 4, 2026 · failed Dec 31, 1969 · NM

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.

Aug 4, 2026 · failed Apr 6, 2026 · NC

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.

Jul 31, 2026 · failed Jul 23, 2026 · GA

High pitched whirring from engine when accelerating. Took to mechanic who diagnosed worn internal transmission bearings that could lead to transmission failure. No warning lights or indicators. Toyota is aware of this issue (see Toyota Technical Service Bulletin T-SB-0008-21) but is doing nothing in response.

Jul 30, 2026 · failed Jul 28, 2026 · ID

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

Jul 29, 2026 · failed Jun 29, 2026 · 62,300 miles · CT

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.

Jul 22, 2026 · failed Jul 16, 2026 · TX

The transmission has failed due to a defect within the transmission. Toyota is aware of the defect but refusing to assist owners claiming warranty expiration despite the transmission failure occurring due to a defect and not normal wear and tear. Toyota service bulletin accepting the defect. T-SB-0008-21

Jul 20, 2026 · failed Jun 23, 2026 · 59,000 miles · NC

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.

Jul 17, 2026 · failed Jun 5, 2026 · FL

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.

Jul 13, 2026 · failed Jul 13, 2026 · CT

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)

Jul 10, 2026 · failed Jun 13, 2026 · NJ

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!

Jul 9, 2026 · failed Apr 14, 2025 · AL

A known issue with this transmission. It started whining and had to be replaced at around 40,000 miles. Was replaced with a rebuilt transmission instead of a new one.

Jul 9, 2026 · failed Apr 3, 2026 · VT

The Automatic transmission is making a whining noise when you press the accelerator. I took it to the dealer and they confirmed it needs a new transmission. the vehicle started making noise at 58,000 miles. When I was able to bring it in it had 60,200 miles on it. They would not cover it under warranty because the 5-year portion of the warranty was up a few month prior. I filed for a goodwill replacement with Toyota and they denied me. Dealer estimate for a replacement was over $8,100 dollars. No warning lights, the problem started with a gentle hum or whine much like a bad pulley bearing then got progressively worse.

Jul 6, 2026 · failed Jun 22, 2026 · FL

Experiencing high pitched whine noise at approximately 65k miles. Local Toyota dealer test drove vehicle, also noticed high pitched whine, and diagnosed as transmission going bad due to issues noted in T-SB-0008-21. Transmission can fail without warning at any time and leave driver stranded or in dangerous traffic conditions with inability to shift gears correctly to get out of harms way.

Jul 6, 2026 · failed Jun 8, 2026 · MI

at 109,000 miles the car started having a whining sound with accelerating. When inspected by the Toyota dealer were told we would need a new transmission. Upon further searching there have been many many reports of transmission failure with the UA80 8 speech automatic transmissions. Toyota is aware of this issue but only a few vehicles have been recalled. It is thought to be a problem with manufacturing.

Jun 26, 2026 · failed Jun 26, 2026 · TX

Vehicle started making a high pitched noise when accelerating at around 98,000mi. I took the vehicle in for the 100,000mi service at 100,854mi and had them also look at this issue. I was told that there was a failure in the front carrier pinion shafts and they recommended replacing the transaxle assembly and rear main seal for $8,354. The vehicle was certified with a 100,000mi power train warranty, but it was just out of warranty. I discovered that there is a class action lawsuit against Toyota for knowingly installing transmissions in 2017 to present vehicles that were known to fail prematurely.

Jun 25, 2026 · failed Jun 24, 2026 · PA

My 2021 Toyota Highlander is experiencing the documented transmission issue impacting vehicles with the UA80E transmission. Our transmission whines and experiences a hesitation or jerks the vehicle. Especially under acceleration. My vehicle was purchased brand new from Toyota. Serviced at a Toyota dealership since purchase.

Jun 24, 2026 · failed Jun 17, 2026 · TX

Transmission started to whine and act erratically during driving. These effects put safety of those in the vehicle at risk by causing distractions to whomever was driving the vehicle, taking their focus off driving. The vehicle was taken to the dealer who confirmed the transmission needed to be replaced due to an internal failure. They said they were able to quickly diagnose this problem because "they saw it a lot." There were no warning lamps or messages from the vehicle.

Jun 24, 2026 · failed Jun 21, 2026 · TN

The transmission is in the whining stage of transmission failure. It has been confirmed by Cumberland Toyota in Cookeville, TN. There were no warning lamps, etc. however Toyota did post a Technical Service Bulletin (TSB) on February 09, 2021 that my vehicle would have transmission issues. My warranty expired the last of April 2026 and I am over the mileage warranty by 800 miles. I recognized the whining on June 21, 2026 and reported to Toyota on June 22, 2026. Toyota knew this transmission was going to fail and most are being reported just outside the 60,000 mile warranty. I have asked for help and assistance from the local dealership as well as corporate, but both have declined to assist.

Jun 23, 2026 · failed Jun 6, 2026 · NJ

Transmission needed! 76,000 miles and Toyota will not address the issue! We have owned Toyotas for 30 some years! Sienna, Avalon, RAV4, Sequoia, and now the Highlander!!!!! There is a massive issue with the transmission across the board in the 2021 and 2022 Highlander and Toyota will not replace.

Jun 23, 2026 · failed Jun 16, 2026 · TN

After just passing 100K miles, there is now a whirling noise upon acceleration. After taking to an auto repair shop, they narrowed it down to the transmission and said it was a known problem (referenced T-SB-0008-21) and suggested I take it to the dealership. I took to the dealership where a service manager offered to ride with me to confirm and he confirmed the issue was in fact the known problem noted from the technical service bulletin. The Toyota dealership assistant service manager stated that the noise (which he said was coming from a final drive gear bearing) would continue to get progressively worse and that despite being a known issue, there was no remediation available aside from replacing the transmission completely. He said that he saw no reason that I could not continue to drive the car without complications and without the transmission going completely out for at least a couple more years, but that the noise would get progressively louder until you could no longer tolerate the noise level and would need a new transmission at that point (despite it just beginning last week (or my just noticing it), you can hear it over the the radio when at a low to moderate volume). If this is a "known issue," (ie: a defect that is only in some of the cars per the T-SB-0008-21 notice) this does not seem like a reasonable answer to 'just wait until you can't stand the noise level with acceleration and then completely replace your transmission as there is nothing we can do for you' but it was suggested that I could take it to a body shop that would rebuild transmissions and they may could replace that part.

Jun 22, 2026 · failed Jun 11, 2026 · MS

I own a 2021 Toyota Highlander with approximately 127k miles. The vehicle has developed a noticeable whining/whirring noise during acceleration. The noise appears to originate from the drivetrain/transmission area and has become increasingly noticeable over time. The condition occurs every-time during acceleration and is present under normal driving conditions. I am concerned that this may indicate a transmission or drivetrain-related issue that could affect vehicle reliability and safety. I have found reports from other 2021 Toyota Highlander owners describing similar symptoms involving whining noises during acceleration. The vehicle has been inspected by a Toyota dealership. And is certified through Toyota. The vehicles was bought new from the Toyota dealership and has had all service done through Toyota. I am submitting this complaint so NHTSA can evaluate whether this condition is part of a broader pattern affecting similar vehicles as a defect in the original transmission built in the SUV.

Jun 19, 2026 · failed Jun 15, 2026 · TN

I own a 2021 Toyota Highlander with approximately 93,000 miles. The vehicle developed transmission symptoms including whining noise. A Toyota dealer diagnosed internal transmission failure and recommended complete transmission replacement at a cost of approximately $9786.31. Toyota declined repair assistance. I am concerned because a transmission failure at this mileage is unexpected and appears similar to other owner complaints involving the 2021 Toyota Highlander transmission.

Jun 17, 2026 · failed Jun 16, 2026 · KY

The transmission in my 2021 Toyota Highlander began producing a whining noise during acceleration between approximately 15-50 mph at around 80,000 miles. The noise stops when the accelerator is released and has progressively become louder. The vehicle was inspected by a Toyota dealership. I was informed that the condition is a known issue affecting some Toyota vehicles, but no repair was offered because the vehicle is outside the 5-year/60,000-mile powertrain warranty. There are currently no warning lights or diagnostic trouble codes. I am concerned that the transmission may fail while driving, resulting in loss of power or propulsion and creating a safety risk for myself and other motorists. The vehicle remains available for inspection.

Jun 17, 2026 · failed Jun 15, 2026 · CA

Transmission makes a metallic whining sound when you accelerate. Associated and confirmed to be transmission failure. Vehicle has 65,000 miles on it and failure is considered premature. The specific transmission, UA80, is known to have manufacturing defects that cause this problem

Jun 15, 2026 · failed Jun 14, 2026 · PA

The vehicle transmission has a distinct whine noise as previous models have had. This is a known issue with these transmissions.

Jun 13, 2026 · failed Jun 13, 2026 · UT

Right after the manufacture warranty of 60K miles, the car began to make a humming noise. I took the car into the dealership with 65K miles on 13 Jun 2026, and the Toyota dealership stated that the humming is caused by the transmission and we will need to replace the entire transmission. The cost would be $9,447.29. This issue is known by Toyota and Toyota put out Toyota Service Bulletin (T-SB-008-21) but failed to issue recall for this defective transmission.

Jun 12, 2026 · failed May 1, 2025 · KY

On two separate occasions I was traveling approx. five to ten miles an hours and had to change lanes. Traffic was heavy and I had to accelerate quickly to do the lane change. The vehicle engine started to rev high and I was barely moving. It was like the transmission didn't know what to do. I had to let my foot completely off the gas for fearing I was going to blow something up. I advised Toyota On Nicholasville several times and they totally ignored me. Also occasionally the transmission will make a clunking noise when shifting in reverse. While this isn't as much of a safety concern as needing your vehicle to respond in traffic and it doesn't. It's very difficult to get Toyota dealers even to document what your concerns are. The way they see it, if wasn't documented, then it didn't happen. The transmission in this vehicle is not safe. You can't rely on the transmission to respond if you are put in a dangerous situation.

Jun 11, 2026 · failed Mar 1, 2026 · OH

My vehicle has 67,100 miles. A whining/whistling noise recently started and the dealer has diagnosed that a new transmission is needed at a cost of $6,000-$8,000 and it is out of warranty. Researching this shows that this is a known manufacturing defect referred to under T-SB-0008-21. I am concerned that my transmission will fail while I am operating the vehicle.

Jun 11, 2026 · failed Jun 1, 2025 · WI

Transmission makes whining noise