2019 Toyota Highlander Complaints

ENGINE — Filed 02/10/2025

I am writing to formally document a series of unresolved mechanical issues with my vehicle, culminating in a complete transmission failure, and to request assistance in resolving this matter. The timeline of events is detailed below: *Winter 2024: I first noticed a persistent buzzing sound originating from the engine compartment. Because this symptom primarily occurred during low ambient temperatures, I initially attributed it to the cold weather. The mileage on this vehicle was around 50k miles. *Spring 2024: I contacted the dealership to report the noise. I was advised that the issue was likely related to a worn belt. Subsequent inspection, however, proved this diagnosis to be incorrect, and the root cause of the noise remained unresolved. *Fall 2024: The engine buzzing returned. Concurrently, a severe driveability issue emerged. On multiple occasions after shifting from Park to Drive, the vehicle failed to engage the gear properly, behaving as though it were in Neutral and preventing any acceleration. This would occur while driving and stopped at redlights, which posed a major safety concern as I was transporting my newborn and young child with me. * February 2025: The vehicle became entirely inoperable. Unfortunately, this failure occurred around 62k miles, AFTER my 60k mile warranty expired, (which i was unaware of). Given that these symptoms began during the winter of 2024 and were reported to the dealership early on, it is clear that the initial diagnostics failed to identify a developing and critical transmission defect. I conducted research and discovered this is a recurring issue with Toyota Highlanders, and other vehicles with the model UA80 transmission. Toyota posted a service bulletin, extending vehicles from 2017 & 2018 but have yet to address the 2019 through current models to date with reports of the same transmission issues.

ENGINE — Filed 04/15/2026

The car is was a 2019 Toyota Highlander with approximately 125,000 miles. White Smoke started appearing in the exhaust. Quickly after that, the check engine light appeared and started blinking, meaning the engine was misfiring. We brought to the dealership, and they found that cylinder 4 of the engine was damaged (scoring on the inside of the cylinder wall). The engine was releasing metal particles in the oil. Further, the cylinder would not hold oil or coolant pressure, and was burning both oil and coolant. The only fix was to replace or rebuild the engine.

POWER TRAIN — Filed 12/10/2025

Hundreds of thousands of 2017–2022 gas-powered Toyota Highlanders (equipped with UA80E/UA80F 8-speed transmissions) are experiencing high-pitched whining noises, hard or erratic shifting, and sudden hesitation. This is caused by a factory defect where a retaining nut and locking tab in the counter drive gear sub-assembly were improperly installed, causing premature internal wear and gear movement

POWER TRAIN — Filed 07/02/2025

I have the high pitch whine coming from transmission. It is a known issue with Toyota but they refuse to look into it since my VIN falls outside their recall list. This is the same transmission as previous years and has the exact same issues. This is a safety issue that needs to be addressed immediately.

VEHICLE SPEED CONTROL — Filed 10/22/2025

Whining sound can be heard while accelerating the vehicle. Maintenance crew is reporting an issue with transmission. UA80F 8 speed transmission on V6 engine in Toyota Highlander has this failure noise. Given that the transmission can fail anytime. It is dangerous to operate the vehicle. No action is taken from Toyota yet.

UNKNOWN OR OTHER — Filed 10/17/2025

Since October 2025 I have had intermittent issues where the car battery suddenly loses power when driving. I have had to pull over on highway medians and shoulders. A few seconds before it loses power, multiple dash alerts go off: pre-collision malfunction, hybrid system malfunction, check engine. It has been seen now by multiple mechanics including Toyota dealership. It is now on its third battery. Replaced yesterday and lost power on highway today. Please investigate this issue.

UNKNOWN OR OTHER — Filed 06/14/2026

The dealership recommended transmission fluid exchange services for my 2019 Highlander SE after the recommended mileage for this service. I wasn’t able to get this service completed because of timing, however later on the service was completed and after three weeks the vehicle started jerking upon acceleration. Took the Benchley back to the mechanic to diagnose the problem. Per the diagnostic test the issue was determined by this code transmission P0745-7F | Pressure Control Solenoid "A" Actuator Stuck Off - Pending DTC.

POWER TRAIN — Filed 06/04/2026

My car has been making a whining noise upon acceleration. It stops whining as soon as you release the acceleration I had a mechanic look at it who verified transmission failure.

UNKNOWN OR OTHER — Filed 05/29/2026

The rear air conditioning refrigerant lines on a 2019 Toyota Highlander SE failed due to excessive rust/corrosion, causing the A/C system to leak refrigerant and stop holding a charge. The failure affected the rear A/C lines that run to the rear of the vehicle. The problem was first diagnosed by an independent repair shop and then confirmed by a Toyota dealer. The Toyota dealer documented that the rear A/C lines were leaking due to excessive rust/corrosion. The dealer recommended replacing the rear A/C lines/cooling lines as a set, evacuating and recharging the A/C system, adding dye, and checking system operation. The repair was completed by the Toyota dealer but not covered or reimbursed. The vehicle/component was inspected by an independent service center and by a Toyota dealer. Toyota corporate customer support was also informed of the dealer diagnosis. The failed component may no longer be available for inspection because the repair has been completed, but repair records, dealer diagnosis, invoice, and related documentation are available. Safety concern: The A/C system failure can affect occupant safety and visibility because air conditioning is used for windshield defogging/defrosting and cabin humidity control. Loss of A/C can reduce the ability to clear the windshield in humid or rainy conditions. It can also create a risk to rear passengers, including children, during hot weather because the rear A/C system is no longer functioning as designed. The failure also involved leaking refrigerant from corroded lines. Toyota will not accept that this is a premature and dangerous parts failure. There were no warning lamps or dashboard messages before the failure. The symptom was that the A/C stopped cooling and would not hold refrigerant. The cause was later confirmed, by Toyota, as leaking rear A/C lines due to excessive rust/corrosion. Toyota has refused goodwill repair even after NUMEROUS persons have reported the same issue online.

POWER TRAIN — Filed 05/22/2026

My Toyota Highlander 2019 began to produce a whining noise that orginates in the transmission at about 89000 miles. An independent mechanic examined the vehicle and deteremined that the noise is well documented. After conducting research, I found that the issue is caused by improper assembly and the only repair is a complete replacement of the transmission. I also discovered that there is a recall on the 2017-2019 Toyota Highlander due to the 8 speed transmission which is also used in my vehicle. The idea that the 2019-2022 Toyota Highlanders are NOT included in this recall is completely unreasonable. These vehicles utilize the same 8-speed transmission and the whining noise tends to surface after 60, 000 miles - about four to five years based on useage. The whining noise began without warning or symptoms. The vehicle drove without issues and we intended on driving this vehicle into retirement considering the reputation Toyota had on building reliable vehicles. I will never purchase or recommend the purchase of a Toyota vehicle! The idea that repeated transmission failures, without an univeral recall for all years affected, shows that the comsumer is not respected. I would enjoy understanding the logic and data that enabled Toyota to limit the recall to just three production year when the 8-speed transmission spanned six years of production (2017-2022). I am now forced to look into replacing the transmission with potentionally another faulty, improperly assembled 8-speed transmission.