2020 Toyota Highlander power train problems

“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…”

“• 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…”

“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.”

“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…”

“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.”

“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”