2020 Toyota Highlander transmission problems

Filed Oct 30, 2026 · Transmission · PA

I am reporting a premature transmission failure in my 2020 Toyota Highlander XLE AWD at approximately 72,000 miles. The vehicle exhibited transmission-related symptoms beginning before I purchased it. During the test drive at Chapman Ford on May 26, 2025, I noticed a whining noise that sounded like it was coming from the transmission. I brought this to the dealership’s attention and was told nothing was wrong. The noise continued after purchase. Over time, the transmission developed increasingly erratic operation and required professional diagnosis. At approximately 71,903 miles, Meenan Transmission documented a transmission whine, erratic operation, diagnostic trouble code P2713-7F (pressure control solenoid D), and transmission fluid containing metal contamination with a burnt odor. Additional diagnostic codes identified during troubleshooting included P0740, P0741, P2756, P2757, P2713 and P2714. The transmission ultimately required complete replacement. The replacement was authorized through a warranty arranged by Chapman Ford. A replacement transmission and additional parts were supplied by Toyota, to my understanding, and installed by an independent transmission repair facility. I am concerned about a complete transmission failure occurring at approximately 72,000 miles, particularly given the prior whining noise and progressive deterioration. I am also aware that Toyota previously established Customer Support Program ZJC for certain 2017–2018 Highlanders and Siennas equipped with UA80 transmissions. That program identified reported symptoms including transmission whining, harsh shifting and reduced power. My 2020 Highlander is not included in that program, despite having experienced a premature transmission failure involving the same transmission family. I am requesting that the federal safety agency document this failure and evaluate whether similar complaints involving 2020 Toyota Highlanders equipped with UA80 transmissions indicate a potential safety-related defect.

Filed Oct 2, 2026 · Transmission · MS

• What component or system failed or malfunctioned, and is it available for inspection upon request? The UA80 8-speed automatic transmission assembly (specifically internal mechanical wear resulting from front carrier assembly bearing degradation/torque converter heat buildup). No, the component and the contaminated transmission fluid are currently being replaced at the dealership. • How was your safety or the safety of others put at risk? The severe mechanical wear and metal-on-metal degradation inside the transmission create an imminent hazard where the vehicle can experience sudden slipping, severe hesitation, or a complete, unexpected loss of motive power while traveling at highway speeds. This loss of acceleration in active traffic creates an immediate risk of a rear-end collision and leaves passengers stranded in an unsafe traffic pattern without warning. • Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. A professional diagnostic inspection confirmed that the transmission fluid was catastrophically low, and the assembly sustained severe internal damage via metal-on-metal contact with metal shavings actively circulating throughout the unit. • Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? The vehicle has been inspected and diagnosed by a service facility. It has not been inspected by the police or insurance representatives, as no crash has occurred yet. However, this failure directly mirrors the mechanical defects acknowledged by the manufacturer in Toyota Technical Service Bulletin T-SB-0008-21 and active federal class-action lawsuits. • Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? There were no electronic dashboard warning lamps or no electronic dashboard warning lamps or visible signs of prior leakage/seepage.

Filed Sep 17, 2026 · Transmission · IA

My Highlander started making a whining noise while accelerating. Took it to my local dealership and was told I need a new transmission. I have 87,000 miles on it! Total cost = $8,000.

Filed Sep 7, 2026 · Transmission · NJ

At 51,000 mile the transmission started making a whining noise. Took it to the dealer and they stated the transmission needs replacement.

Filed Sep 4, 2026 · Transmission · NC

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 the federal safety agency or other appropriate parties if requested before the repair is performed.

Filed Sep 1, 2026 · Transmission · KS

The transmission started making a whining noise around 69,000 miles that a mechanic said was due to transmission failure. There were no warning lights or messages. I took it to the Toytota dealer who sold it to me new. They inspected it and confirmed that the transmission needed replaced which they did. Online research said these symptoms meant the transmission could fail at any time while driving it which could put passengers and others at risk.

Filed Aug 28, 2026 · Transmission · CA

The transmission had a catastrophic failure at 73,000 miles and six years after purchase. There has been a service bulletin issued with known defects on this transmission yet Toyota corporate failed to acknowledge that they installed faulty transmissions in the 2020 Toyota Highlander. The diagnosis was a failed pinion bearing which the dealer diagnosed to replace the transmission at nearly $10,000

Filed Jul 29, 2026 · Transmission · MD

We have a 2020 Toyota Highlander with 89K miles that we have owned since it was new. I was informed today to not drive it any long distances from the dealer due to an impending failure of the transmission, creating a large safety issue for me and my family. I understand there are related recalls of the UA80 transmission but none for this particular model; there are countless internet reports of failure. I implore the federal safety agency to investigate and protect the motoring public.

Filed Jul 7, 2026 · Transmission · CA

Transmission stalls in situations where speed is needed. For example when merging into traffic all of a sudden no power then when gear finally engages there a huge thump and feels like being hit from behind.

Filed Jul 7, 2026 · Transmission · NH

The transmission can suddenly fail even at very early mileages. This is almost certainly related to T-SB-0008-21 that has defined a narrow number of transmissions though it appears to affect many more than outlined. This could cause sudden failure while operating the vehicle at any point in time and potentially lead to a crash without much if any warning. Toyota Brand Engagement is denying any assistance due to external service history from a prior owner rather than addressing the failed part outlined in the TSB. Failure reasoning cannot be provided from the dealership as Toyota does not allow the dealer technicians to open the transmission and instead mandate a full replacement.