2020 Toyota Highlander Power Train

2020 toyota highlander l Transmission..whining noise it gets louder when accelerating

TRANSMISSION GAVE OUT

Transmission failure. Noticed whining when driving, took to local Toyota dealership and they diagnosed transmission failure. They quoted $12,000 for transmission replacement and confirmed that this is a known issue with certain years/models of Toyota Highlander. Ours is a 2020.

Around 92k miles my transmission started makining a whining noise while driving. Dealership diagnosed a transmission problem and it needed to be replaced. They said eventually the transmission will go bad and stop working, potentially leaving me stranded or causing an accident. Spoke with Toyota HQ who would not offer financial assistance or assist with getting a part. UA80F transmissions are on a nationwide backorder. They also would not acknowledge that there is a problem.

Transmission failure at 78,000 miles

Transmission Planetary Gears in 2020 Toyota Highlander. Makes a "whining" noise when accelerating. No warning lights or other symptoms. Many reported problems with this model but no recall. Many people are needing to pay out of pocket due to the 60k mileage powertrain warranty.

UNKNOWN, dealers are reporting 1-2 2020-2022 Highlanders are needing completely transmission replacements at 8-10k in cost. They are all failing and toyota knows this.

Whining noise upon acceleration, replacement transmission recommended by Toyota dealer. Defective UA80F installed.

My wife was driving on the highway, felt a bump and the engine RPMs spiked. The check engine light came on as well as a error message that the secondary collision braking system was disabled. The vehicle was taken to the dealership and we were told there was a internal failure in the transmission. The vehicle has approximately 80K miles.

UA80E or UA80F Toyota transmission require a complete replacement at 65K miles. Not covered under warranty or Technical Service Bulletin T-SB-0160-18, T-SB-0008-21

I am filing a complaint with the NHTSA regarding persistent transmission slipping in my 2020 Toyota Highlander LE equipped with the UA80-E 8-speed automatic transmission. Since reaching approximately 55,000 miles, I have experienced noticeable slipping, characterized by delayed acceleration, erratic shifting, and occasional lurching, which align with documented defects in the UA80 platform as outlined in over 430 NHTSA complaints and Toyota’s Technical Service Bulletins (e.g., T-SB-0160-18 and T-SB-0008-21). These issues stem from a known manufacturing flaw involving a washer tab failing to secure the counter drive gear’s retaining nut, leading to gear movement, internal wear, and symptoms like mine. This defect, prompting Toyota’s Customer Support Program ZJC for 2017–2018 models and reported in later years like 2020, compromises vehicle safety and reliability, as slipping can cause unpredictable handling. I urge the NHTSA to investigate further and hold Toyota accountable for addressing this widespread issue across affected models.

At approximately 72,000 miles, my 2020 Toyota Highlander Platinum was diagnosed by my dealership with a failing transmission that requires full replacement. I first began hearing a high-pitched whining noise during light acceleration shortly after a routine oil change, at some point between 60,000 and 70,000 miles. I did not immediately recognize it as a drivetrain issue until the symptoms worsened. This model uses Toyota’s UA80 8-speed automatic transmission, which has been the subject of Technical Service Bulletin T-SB-0008-21 and a Customer Support Program (ZJC) for earlier Highlander models due to similar internal component failures. Despite clear continuity in the symptoms and transmission design, Toyota has not extended coverage or issued a recall for 2020 models like mine. The failure occurred shortly after the end of the 5-year/60,000-mile powertrain warranty, but symptoms began while the vehicle was still within warranty range. Toyota has not responded to my formal escalation through Customer Care for nearly three weeks. I am deeply concerned Toyota is not addressing what appears to be a systemic and known defect in a critical drivetrain component that can jeopardize vehicle safety. There was no warning light or dashboard alert at the time the failure developed, making this both a mechanical and safety concern. While this issue does not involve a catastrophic failure like the Takata airbag recall, Toyota’s lack of response to a known, widespread transmission issue raises broader concerns about safety, transparency, and accountability. A sudden transmission failure—particularly at highway speeds—could result in loss of power or control. Given that several owners have filed similar complaints, I respectfully urge NHTSA to investigate this issue further and assess whether Toyota should issue a recall or expanded service campaign for 2020 Highlander models equipped with the UA80 transmission, particularly in light of prior coverage for earlier model years.

Transmission failure- this affects the safety of others when the car decides it doesn’t want to accelerate and could potentially lead to car accidents when another vehicle runs into it. The transmission needs to be completely replaced. This issue started back in January and has been an ongoing problem since warranty and Toyota will not assist with issue of their faulty product.

Transmission making whining noise that increases with speed. Concerned about safety if transmission fails while driving Diagnostic done at Toyota and confirmed transmission is failing and needs new replacement. There are no warning lamps. Noise has increased intensity over short period of time

At around 61,000 miles, I noticed a whining sound in the vehicle when accelerating. I took the vehicle in to a Toyota dealer for diagnostics and their technicians indicated that my vehicle had transmission failure and it needed to be completely replaced - quoted at $8,000 to do the replacement. Diagnostic appointment also cost $174. Parts are on back order and no one could tell me when parts would come in - guess was one month. In reality, parts are now finally in (I'm about to take it in to be fixed) after 2 months. I was told by the dealership that I could drive it at my own risk of failure - if it were to fail, I would be stranded wherever that may be putting my family and those around me at risk due to the unknown nature of when that could happen. This failure is recorded for the same model and same UA80 transmission on several online forums: [XXX] The vehicle has been inspected by a Toyota dealer as I stated previously. Diagnostic report says "Internal component failure. Recommend transmission" No other warning lights or messages from the car to warn me of this problem even now. Just the whining sound from the failure itself. Keep in mind, Toyota's powertrain warranty period is 5 years or 60,000 miles - this vehicle just surpassed both of those limits as this problem came about. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The transmission started slipping without any warning and then went into neutral while driving and I am not able to drive it anymore. The dealership said the transmission is bad. I see many complaints online about 2020 Toyota Highlander transmissions going bad for no reason. This is a new car only 4.5 years of normal driving and the transmission goes, this is not normal for such a high rated vehicle.

8 speed automatic transmission started whining at 45k miles (purchased new), has been inspected, dealer confirmed transmission is bad and part is on back order (date keeps moving out),

Began hearing a high-pitched whining sound when I accelerated. Took it into the dealer and they casually told me that I needed a new transmission. My car was less than four years old, but had more than the 60,000 miles that would apply under a warranty. I am now reading online. This is a widespread problem involving Toyota Highlanders. Can’t get a new transmission for three months or more.

76,000 miles on my 2020 Highlander. Car was made in September 2020, less than 5 years old. Started to hear whining noise from transmission. Over past few days it has gotten louder. Took to Serra Toyota dealer today in Birmingham, Alabama. They confirmed a problem with transmission and told me I needed a new one for $8600. None are even available. I refuse to pay Toyota any money for this. This is a KNOWN issue with the UA80E transmission. The transmission may completely stop working at anytime now. Dealer was unwilling to do anything to help me since car is out of 60,000 mile warranty, and no TSB's or recalls are for my particular year 2020. There is a TSB for 2021 UA80E transmissions. I am so angry about this. This is a clear manufacturing defect. When this transmission dies which will be sooner than later the car will be worthless with no transmissions available.

My 2020 Toyota Highlander Platinum started having the well-known "whining" sound at just under 60,000k. This is coming from the transmission. The vehicle is now just over 60,000k and I did not know that the noise was a cause for concern, let alone something that was an issue (I am not tech savvy - I'm just a regular person). I will not drive this vehicle again, as it is my only transportation for my children. Toyota issued a service bulletin about this issue for 2021 Highlanders ONLY, but as I am now experiencing this problem, I see that this is something well known as a problem.

Final drive failing in transmisssion

At about 85,000 miles, the transmission developed a whine noise, and two dealers and a transmission shop all state it needs replacement. However, the backlog for replacement is enormous and I risk the transmission failing catastrophically while driving.

The contact owns a 2020 Toyota Highlander. The contact stated while driving at undisclosed speeds, there was a whining sound coming from the transmission. There was no warning light illuminated. The vehicle was taken to a local dealer where the vehicle was diagnosed, and the contact was informed that the internal bearings had failed, and the transmission needed to be replaced. The vehicle was not repaired. The contact referenced Technical Service Bulletin: TSB-0008-21 as a possible cause for the failure. The manufacturer was notified of the failure. The approximate failure mileage was 99,000.

There is a whining noise coming from the power train/transmission. It only happens when the accelerator pedal is pressed. We had a couple of mechanics look at it. The transmission oil was changed twice, with the vehicle less than 78,000 miles. Neither mechanic can find any issue with any other item, including the engine. The noise still persists. There are no warning lights on. We have researched the web. Toyota is aware of the problem and has replaced some transmissions still under warranty. They have issues a TSB (TSB008-21) in February 2021, but did not issue a recall or notify owners of a potential problem.

The transmission is making a whining noise at 104;368 miles. We own another 2020 Toyota Highlander and it had to have the transmission replaced for the same reason. It is available for inspection. It’s a safety hazard because it’s a bearings in the transmission that’s failing. The transmission will eventually stop working. The issue was confirmed by a Toyota dealer and one of our transmissions has already had to be replaced. Toyota has a service bulletin out for this known problem. There were no warning signs for the transmission noise.