2021 Toyota Highlander: transmission slipping

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 Jun 25, 2026 · Driver assistance · AZ

2021 Toyota Highlander UA80 transmission failed at 100,000 miles. Codes P2808, P0741. Matches Toyota TSB-0160-18 and T-SB-0008-21. Dealer Alexander Toyota and TMS Brand Engagement denied goodwill. TMS rep stated "TSBs don't matter" despite pending class action Pallaya v Toyota, Case 2:25-cv-10458, which cites these TSBs as proof Toyota knew of defect. Toyota refusing to honor documented defect. Transmission slip/loss of power is safety issue. Request investigation.

Filed Nov 20, 2025 · Engine, Transmission · PA

Almost caused high speed accident merging onto toll road! The vehicle is experiencing a severe transmission slippage, shudder, and grinding noise, consistent with TSB-0008-21 (UA80 transmission failure). This defect causes hesitant acceleration and erratic shifting, creating a safety hazard when merging onto highways or crossing intersections. I am concerned the transmission will fail completely while driving, resulting in a sudden loss of motive power and increasing the risk of a crash. Toyota has covered this exact safety defect in 2017–2019 models (CSP ZJC) but has failed to recall the 2021 models despite identical symptoms. First reared it's head as slipping when putting vehicle in reverse, 25k+ ago. Was told by Toyota Certified mechanics it was an operator error. Morphed into larger issue.

Filed Oct 14, 2025 · Transmission · IL

Slipping and Whining transmission while driving in the Ozark mountains on [xxx]. I didn't feel I had full control of the vehicle. No warnings of any kind. Took the vehicle to Saint Charles Toyota service department on 10/2/25 where a bad transmission diagnosis was confirmed. Regards, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 8, 2025 · Transmission · MO

Transmission began producing a whine sound at 58k and slipped several times.. A transmission that slips could cause a wreck involving all passengers. Requires replacement. No warning lamps. Show some integrity Toyota and stand behind your products.

Filed Oct 7, 2025 · Transmission · SC

66,564 Miles, Transmission slipped and caused a delay in power, now it has a big high pitched whine and continues to do it. This looks to be a big problem across the board for 2021 Highlanders.

Filed Sep 10, 2025 · Transmission · TN

Transmisson started whining and slipping at 61000 miles. 1k miles out of warrenty. Even though toyota has a service bulletin about knowing my exact year and serial number transmisson will go bad. No recall issued and they want 9k for a repair. Rick McGill toyota on alcoa highway knoxville tennensse diagnosed it.

Filed Sep 7, 2025 · Transmission · WI

Transmision is whining and stuttering or slipping gears

Filed Jun 3, 2025 · Engine · MS

I am seeing a transmission slip and also engine whining noise. There is a widely known issue with this transmission failing. My serial number A3A20M01780 falls right outside the scope of the TSB issued by Toyota for these transmissions.

Filed Aug 22, 2024 · Transmission · CA

Transaxle Repair/Replacement: recommend transmission replacement due to whining noise coming from transmission due to internal failure. The transaxle is the transmission for front wheel drive vehicles. The transaxle transfers power from the engine to the wheels. Unsafe driving conditions issue is stemming from faulty transmission, not only on this particular vehicle but many 2021 Toyota Highlander vehicles for the same transaxle repair/replacement issue. I have gone to Toyota multiple times before and even with a Technical Service Bulletin in place for this transmission issue, they did not correct the problem, nor fix it while it was under warranty. Toyota has been aware of this Technical Service Bulletin since Feb 9 2021. T-SB-0008-21 [XXX] Owners of the 2021 Toyota Highlander have reported various transmission problems, including: Whine or Grind Noise: Some vehicles exhibit a whine or grind noise from the transmission, which may be caused by an issue with the front carrier assembly pinion shafts1. Jerky Gear Shifts: Drivers have experienced jerky gear shifts, especially when accelerating from a stop or slowing down to very low speeds2. Delayed Shifts and Hard Shifts: There have been complaints about delayed shifts, hard shifts, and lurching when shifting gears3. Transmission Slipping: Instances of the transmission slipping between gears and jerking when accelerating have also been reported4. Safety Concerns These transmission issues pose several safety risks: Loss of Control: Jerky and delayed gear shifts can lead to a loss of control, especially in situations requiring quick acceleration or deceleration. Increased Accident Risk: Transmission slipping and hard shifts can cause unexpected vehicle behavior, increasing the risk of accidents. Driver Distraction: The noise and irregular shifting can distract drivers, reducing their focus on the road. Mechanical Failure: Persistent transmission issues, or stalling. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)