1,021 of the 7,196 complaints filed about the Toyota Highlander are about the transmission — 100% of everything owners reported. The worst model year for it is 2021.
1,021
Complaints
100%
Share of all complaints
29
Crashes
1
Fires
POWER TRAIN
Whining noise in the transmission
NHTSA complaint #11764063 — an unverified report by a vehicle owner.
POWER TRAIN
My 2019 Highlander was driving totally normal, when all of a sudden the transmission started slipping and then would no longer accelerate. I was on a windy back road in Alaska with no service, so after letting it sit for a bit I tried to drive it again. It then drove maybe 1/2 more miles before slipping completely and no longer accelerating. No check engine lights came up. I got it towed to my house where a mechanic took a quick scan and said there was a number of transmission codes popping up.
NHTSA complaint #11764218 — an unverified report by a vehicle owner.
POWER TRAIN
Transmission Failure Yes TSB No Warning Lights
NHTSA complaint #11764003 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11764197 — an unverified report by a vehicle owner.
POWER TRAIN
While accelerating, the vehicle produces a loud whining noise from the transmission area underneath the vehicle. I took the vehicle to Modern Toyota in [XXX] on XXX at 103,287 miles. The dealer diagnosed the condition and their invoice states the vehicle "needs the transmission replaced due to a gear whine." The estimated repair cost is approximately $10,498. This vehicle is equipped with the UA80E 8-speed automatic transmission. Toyota documented this same condition in Technical Service Bulletin T-SB-0008-21, which describes a whine or grind noise from the transmission caused by the front carrier assembly pinion shafts, and prescribes transaxle replacement as the repair. My vehicle exhibits the identical symptom and requires the identical repair. The vehicle is the original purchase, bought new on XXX. The failure occurred outside the 60,000-mile powertrain warranty limit, leaving the full repair cost to the owner. This appears to be a widespread defect affecting UA80-equipped Toyota vehicles across multiple model years, and I am reporting it so it is on record. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11764141 — an unverified report by a vehicle owner.
POWER TRAIN
There is an unknown whine coming from the transmission when pressing on the throttle. It loud and high pitched.
NHTSA complaint #11763567 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11763402 — an unverified report by a vehicle owner.
POWER TRAIN
About a few weeks back we started noticing a whining noise while accelerating. For safety reason we are not using the truck for long distance driving. Yes, the problem was able to reproduce by an independent mechanic and confirmed. Has not been inspected by the manufacturer or any other. There are no warning lights on the dashboard.
NHTSA complaint #11763061 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11763069 — an unverified report by a vehicle owner.
POWER TRAIN
Transmission failure at 80,000 miles
NHTSA complaint #11763132 — an unverified report by a vehicle owner.
POWER TRAIN
UA80 Transmission failure. Was driving on highway when the transmission failed and lost power to the vehicle. Car was taken to Sunshine Toyota (Batte Creek MI) in 2022 and the transmission was recommended to be replaced due to a defect at 67,000 miles. The car was then sold off, and I acquired it through another dealer.
NHTSA complaint #11762738 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11762799 — an unverified report by a vehicle owner.
POWER TRAIN
At 51,000 mile the transmission started making a whining noise. Took it to the dealer and they stated the transmission needs replacement.
NHTSA complaint #11762589 — an unverified report by a vehicle owner.
POWER TRAIN
**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.
NHTSA complaint #11762480 — an unverified report by a vehicle owner.
POWER TRAIN
Transmission failure at 106,000 miles, full replacement under extended warranty and new transmission is begging to fail at 109,000 miles.
NHTSA complaint #11762462 — an unverified report by a vehicle owner.
POWER TRAIN
The transmission (power train) in this vehicle shows symptoms of a known defect in Toyota's UA80 8-speed. Since approximately (Aug 2026/~70k mileage), it has produced shining/grinding noised at increasing speed. these symptoms match failure patterns described in Toyota's own Tech Service Bulletin for transmission, which have led to documented cases of sudden power loss, gear slippage, and complete failure in other owners of this and related models. I have not yet experienced complete loss of propulsion, but given the documented failure patterns, there is a foreseeable risk this could occur without warning while driving, including traffic or while merging, creating a safety hazard. I took the vehicle to Toyota of Manchester, NH dealership on [XXX] and requested repair given the known TSB coverage. Toyota denied repair assistance, citing lack of dealer service records, despite transmission fluid being a lifetime-fill component unrelated to this failure mode. I am filing this proactively due to the documented risk of sudden failure, and because Toyota denied to address a known, symptomatic defect before it progresses and declined to take responsibility for the repairs or repair assistance for this defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11762379 — an unverified report by a vehicle owner.
POWER TRAIN
My 2020 Toyota Highlander XLE AWD developed a high-pitched whining noise from the drivetrain/transmission area while accelerating. The noise increases under acceleration and stops when the accelerator is released. The noise is not present when the vehicle is in neutral. I brought the vehicle to an authorized Toyota dealership for diagnosis. The dealership confirmed the condition and determined that the transmission requires replacement. The vehicle had only recently exceeded 60,000 miles when the problem was diagnosed. My safety concern is that this appears to be an internal transmission failure occurring at relatively low mileage. Because the transmission is a major drivetrain component necessary to maintain propulsion, I am concerned that continued deterioration could result in loss of propulsion or a more serious transmission failure while the vehicle is being driven. Toyota has reviewed the dealership's diagnosis and has approved supplying a replacement transmission through goodwill assistance. The original transmission has not yet been removed and remains installed in the vehicle. I am reporting this condition because I have identified other complaints involving Toyota Highlanders with similar transmission whining under acceleration and subsequent transmission replacement. I am concerned that this may represent a recurring transmission defect rather than an isolated failure. Because the original transmission is still installed, the vehicle and transmission should currently be available for inspection by NHTSA or other appropriate parties if requested before the repair is performed.
NHTSA complaint #11762141 — an unverified report by a vehicle owner.
POWER TRAIN
Car started to have a whining noise only when accelerating at 122,000 miles took it to the Toyota dealer where I bought it from. They did a diagnostics and told me it was the transmission and that it cost almost 10,000 to fix it. Car did not have no check engine light at all.
NHTSA complaint #11762285 — an unverified report by a vehicle owner.
POWER TRAIN
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.
NHTSA complaint #11761897 — an unverified report by a vehicle owner.
POWER TRAIN
The UA80 8-speed automatic transmission failed at 87,896 miles. Symptoms began as slipping in 1st and 2nd gears and harsh jerking when accelerating from a stop, with the engine revving while the vehicle failed to move. This is a loss of motive power that can occur without warning in traffic. On 8/31/2026 a Toyota dealer diagnosed a failed transaxle requiring complete replacement, with a whine traced to the differential inside the transmission, and quoted $11,126.81. This matches the failure mode in Toyota TSB T-SB-0160-18, which Toyota addressed for some 2017-2018 VINs under Customer Support Program ZJC. My 2019 has the same UA80 unit but falls outside that program. The replacement part is backordered with no ETA per Toyota's own case portal. The vehicle is maintained on schedule and available for inspection. Toyota declined goodwill assistance and refused to provide the denial in writing.
NHTSA complaint #11761588 — an unverified report by a vehicle owner.