2018 Toyota Highlander power train problems

“UA80 transmission which has known issues failed. Dealer reports that while the transmission has exact symptoms of other UA80 transmission that are covered under recall, our serial number is not covered. Quoted $12454 to replace transmission that has known failure issues”

“Within 1 mile of the Dealership, the new to us, 2018 Highlander was: -Lunging, not accelerating/Delayed shifting -Unpredictable surging -unintended acceleration -Excessive revving before upshifting I brought it back to the dealership & was given a loaner vehicle Once the transmission line was supposedly fixed, I drove it home. Then discovered it had leaked onto my driveway. They took it back & fixed something in the transmission again. After a few months, we thought it was good to go. In October 2026 it was doing all of the above lunging, lack of response from Transmission Again. I drove it to the dealership. Then told I needed a replacement Transmission. They said line rusted and was leaking. I have been asking if they have pictures from prior services. I have continually gotten under body washes & don’t believe that it started rusting while I was the owner. This transmission is obviously defective like the ones in class action lawsuits. I have called the dealer & now Toyota Customer Care to discuss them doing the right thing. Which I believe would be them taking responsibility and paying for the new transmission. It has been a month of waiting for a transmission to be located.”

“While driving, my vehicle experienced a severe and sudden failure of the Aisin UA80F 8-speed automatic transmission. The transmission exhibits erratic and hard shifting, severe hesitation, and a dangerous delay in acceleration when trying to merge into traffic or accelerate from a complete stop. Frequently, the engine revs high, but the transmission fails to engage the gear promptly, resulting in a sudden, violent lurch forward when it finally catches. Furthermore, the vehicle intermittently loses motive power entirely while in motion, forcing me to coast to the side of the road. A loud, high-pitched whining noise is audible from the transmission assembly, and diagnostic checks indicate internal mechanical overheating and premature component wear.”

“My transmission had to be replaced at 30,000 miles and a year and two weeks later it needs replaced again at 42000 miles. Toyota will only cover 1/2 the replacement the second time and nothing the first.”

“I took my car in to the dealer for a noticable hum sound that was staying to occur. UA80 transmission model has been determined to be failing by the dealership that I took it to. They determined there's metal flakes showing in the fluid.”

“The contact owns a 2018 Toyota Highlander. The contact stated that while driving 75 MPH, there was an audible chime followed by the message "Transmission Overheating". The vehicle started jerking and hesitating while depressing the accelerator pedal. Additionally, there was a burning odor coming from the vehicle. Due to the failure, the contact pulled off the highway and allowed the transmission to cool down. The vehicle was restarted, and the message disappeared; however, the vehicle continued to hesitate while depressing the accelerator pedal. The contact continued driving 70 MPH, and the transmission message displayed again. The vehicle was then taken to a dealer, and the failure was associated with Customer Support Program: ZJC. The contact was informed that the vehicle was not included in the program. The manufacturer was notified of the failure, and the contact was provided a case number. The manufacturer confirmed that the vehicle was not included in the CSP. The failure mileage was approximately 130,000.”