2020 Toyota Highlander

On September 2, 2025, the vehicle’s Hybrid System shut down on cold start and the vehicle would not start. A dealer inspection reported coolant had entered cylinder #4, allegedly causing the engine block to warp, the cylinder head to crack, and the head gasket to fail. This was a sudden catastrophic engine failure on a five-year-old vehicle with no prior overheating warnings, no dashboard alerts, and no performance issues in the days leading up to the failure. It is highly unlikely for an engine block to warp without sustained overheating, yet the failure occurred on a cold start. The dealership itself described this as a “premature failure” in their service report. At approximately 26,000 miles, the vehicle’s coolant thermostat failed and was replaced under warranty. If the thermostat stuck closed even briefly, the engine could have experienced one or more silent overheat events that never registered on the dashboard. In aluminum blocks, even short bursts of high localized heat can create latent distortion that doesn’t cause immediate problems but can eventually lead to catastrophic failure years later. Safety Risk: – Vehicle became disabled suddenly without warning. – Engine failure occurred without overheating symptoms, creating risk of sudden shutdown during use. Problem Confirmation: – Engine failure confirmed by a Toyota-authorized dealer. – Dealer service report explicitly called this a “premature failure.” Warning Lamps / Symptoms: – A check engine light appeared briefly three days before failure, then cleared on its own. – No overheating warnings or drivability issues were observed prior to failure.

The contact owns a 2020 Toyota Highlander. The contact stated that while driving at 30 MPH, there was an abnormal whining sound coming from underneath the vehicle. No warning lights were illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the transmission. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 78,000.

All of the sudden around 70K miles, the transmission started to make a "whining" noise. It does not sound right and I'm afraid the transmission could fail while I'm driving. I took it to the dealer and they acknowledged that it's a known issue but that in my case the noise is not loud enough to warrant replacing the transmission. A quick research on the internet revels that this is a very common problem.

My 2020 vehicle has 75,000 miles on it. It started making a high pitched sound when accelerating. I brought my vehicle to the dealership where I bought it, to have it inspected. I was assuming it would be a belt or an easy fix. The service agent walked over and cooly explained that I need a new transmission. He continued to say that this is a common issue with this make and model. He stated that at the beginning of the year customers were having to wait a couple of months of transmission parts, but now because of the demand due to the well known power train failure, that the current wait time for transmission parts are only two weeks. He stated several times, that this is a common problem, one that car owners are expected to pay $9,000. to fix. A quick google search brings up a plethora of customers having the same exact problem. Toyota needs to make this right and issue a recall on their faulty product.

Vehicle: 2020 Toyota Highlander XLE VIN: [XXX] Mileage (approx): 78,000 Problem Description: My vehicle displays an SRS Airbag System Malfunction warning and a seatbelt chime that activates whether the passenger seat is occupied or not, and whether the buckle is latched or not. The chime stops after about a minute, but the SRS light remains on. This behavior matches a false passenger occupancy detection, which suggests the Occupant Classification System (OCS) sensor is still malfunctioning. My vehicle was included in Toyota Recall 23TA15 (NHTSA 23V865), and the dealer (Classic Toyota of Hampton) marked the recall as completed on September 9, 2025. However, the current symptoms are identical to those described in the recall, which indicates the recall remedy may not have corrected the defect. Toyota now claims the issue is due to the passenger seat buckle, but a buckle alone would not cause the system to chime when the seat is empty. I believe this is a continued failure of the OCS system, which directly affects the airbag and seatbelt safety system. Safety Concern: The ongoing fault may cause the passenger airbag to deploy incorrectly in a crash. I am concerned that the recall remedy was ineffective, leaving my vehicle unsafe. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The vehicle’s transmission makes an audible whining noise during acceleration and intensifies as the car increases speed. The vehicle has been diagnosed and inspected at the original dealer where the car was purchased and confirmed that the transmission needs to be replaced. The vehicle’s powertrain warranty has just expired and this issue is a major problem and concern with similar model years.