2021 Toyota Highlander: grinding or squealing brakes

Filed Oct 4, 2026 · Transmission · MO

We bought a 2021 Toyota Tacoma Platinum in November 2020. In February 2021, Toyota issued a Technical Service Bulletin T-SB-0008-21. The bulletin say transmissions may exhibit a whine or grind noise from the transmission. This condition may be caused by an issue with the front carrier assembly pinion shafts. This bulletin says repair is covered under the Toyota Powertrain Warranty. This warranty is in effect for 60 months or 60,000 miles, whichever occurs first, from the vehicle’s in-service date. Our transmission began making this noise around 75k miles, outside the warrant. Toyota knew about this problem over 5 years ago and did not take action to recall it. Now this repair is going to cost between $9,000 to $12,000 out of pocket. I cannot afford this repair. I have uploaded the bulletin from Toyota.

Filed Sep 30, 2026 · Engine · KY

I own a 2021 Toyota Highlander Platinum AWD equipped with the 3\.5L V6 and approximately 77,000 miles\. The vehicle developed a humming/whining, airplane\-like noise from the front drivetrain while accelerating\. The noise increases with vehicle speed and stops when the accelerator is released\. There is no vibration, and the vehicle makes the same noise while traveling straight\. I took the vehicle to an authorized Toyota dealer, Kerry Toyota, and the dealer diagnosed the transmission as the source of the noise and recommended replacement of the transmission\. The quoted replacement cost is approximately $7,600 plus tax\. Toyota previously issued Technical Service Bulletin T\-SB\-0008\-21 concerning a whine or grind from certain 2021 Highlander UA80 transmissions and identifying the front carrier assembly pinion shafts as a potential cause\. My vehicle is approximately 17,000 miles beyond Toyota’s 60,000\-mile powertrain warranty\. I contacted Toyota requesting goodwill assistance with the transmission replacement, and Toyota declined assistance\. I believe there may be many similar cases involving 2021 Toyota Highlanders equipped with the UA80 transmission, including vehicles experiencing comparable whining or grinding noises and premature transmission\-related failures\. I am reporting this because an internal transmission problem that develops shortly beyond the powertrain warranty may worsen and could potentially result in loss of vehicle propulsion\. I believe the federal safety agency should review this issue along with similar complaints involving 2021 Toyota Highlanders equipped with the UA80 transmission\.

Filed Sep 9, 2026 · Transmission · 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.

Filed Sep 8, 2026 · Transmission · 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.

Filed Sep 6, 2026 · Transmission · 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 the federal safety agency'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.

Filed Sep 2, 2026 · Body, Transmission · 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.

Filed Aug 4, 2026 · Transmission · 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.

Filed May 26, 2026 · Transmission · CA

I own a 2021 Toyota Highlander with approximately 100,500 miles. The vehicle has developed a noticeable whining noise coming from the transmission/drivetrain area that continues to worsen over time. The noise is most noticeable during acceleration and while driving at highway speeds. I brought the vehicle to Toyota for inspection and was informed that the issue is related to the transmission. However, Toyota denied repair assistance because the vehicle is outside the powertrain warranty period. After researching the issue, I discovered multiple similar complaints involving 2021 Toyota Highlanders equipped with the UA80 transmission, including Toyota Technical Service Bulletin T-SB-0008-21 regarding “Whine or Grind Noise From the Transmission.” The symptoms described in the bulletin closely match the symptoms my vehicle is experiencing. Toyota appears aware of this transmission-related issue, yet many owners outside the warranty period are being denied coverage despite similar failures and complaints. I am concerned this may represent a broader transmission defect that could lead to premature transmission failure, unsafe driving conditions, hesitation, loss of power, or expensive repairs for consumers. I believe this issue should be investigated further by the federal safety agency due to the growing number of similar complaints involving whining transmission noises and transmission failures in Toyota Highlander vehicles. At this time, the vehicle has not yet experienced a complete transmission failure, but the condition is worsening and raises significant concerns regarding reliability and safety.

Filed May 16, 2026 · Transmission · MA

2021 Toyota Highlander XSE AWD with approximately 60,400 miles. Vehicle has developed a noticeable driveline/transmission humming/whining noise during acceleration, beginning at lower speeds and increasing with vehicle speed under throttle. Noise is most noticeable while pressing the accelerator and appears consistent with Toyota T-SB-0008-21 regarding transmission whine/grind concerns on UA80F transmissions.

Filed May 13, 2026 · Transmission · CO

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 the federal safety agency investigate the widespread transmission failures affecting 2021 Highlanders and related Toyota vehicles.

Filed May 5, 2026 · Transmission · PA

I noticed transmission whining shortly after purchasing on 3/12/24. Odometer reading at purchase 62,347. I justified whining to myself as luck of the draw. Until a few months ago I started hearing grinding noise coming from the transmission. Had transmission diagnosed at Lancaster Toyota on 4/22/2026. Approximate odometer reading, 78,700. Was told that a replacement transmission was needed. Cost 9,526.17 No warning lamps or messages appeared. Transmission type UA80F SN A4A20J O 4195

Filed Apr 27, 2026 · Transmission · TX

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 federal safety agency 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.