2017 Toyota Highlander

Was on drive from work in 2017 toyota highlander XLE. Noticed low whining sound coming from transmission. Made appointment with toyota dealership. They identified transmission whine as requiring full replacement and projected to fail soon. Vehicle mileage was at 116k miles. There are no ua80 trans available in US and none coming in. Was told my VIN didn't qualify for CRP CJZ and TSB bulletin. The UA80 trans has known failure of this type. Replacement cost is 10K, use is dangerous, and failure is unacceptable.

The contact owns a 2017 Toyota Highlander. The contact stated that upon taking the vehicle to an independent mechanic for service, the contact was informed that the engine was leaking due to a timing chain failure. The contact was advised that the engine needed to be taken apart to repair the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was filed. The failure mileage was approximately 60,000.

After less than a year of usage on a Highlander with 70k miles, the transmission began malfunctioning. The reverse function would work sporadically. The gears would shift only when using the power stick function and manually switching gears. The transmission would go into overdrive and once after an oil change the car came to an abrupt stop after traveling 25 mph hour.

The transmission is experiencing harsh and sometimes delayed shifting and sometimes reduction of power. This can result in unpredictability when going from a stop and then crossing traffic. If the transmission fails while I am making an unprotected left turn it pups leave me vulnerable to side impact from on coming traffic. The dealer was able to reproduce the issue when I took it in and quoted me $11k for repair. Toyota is an aware of issues with this specific transmission (UA80) and issued a Service Bulletin for it. My transmission fell within the serial number range for replacement but didn’t pass the third gate for coverage related to a speed sensor issue. That said, there is massive back order on this transmission highlighting a much broader problem with the part. To answer the final question, I never saw a warning light.

My vehive has 122,000 miles...I recently received an airbag mafuction warning on the dash info system and to contact dealer. The dealer states this driver side airbag is now defective and needs to be replaced at a cost of $1100.00 The airbag has never been deployed. How is this noit covered under safety requirements on current vehicles? How do I know that the part was not defective when initally installed?

Formal Complaint to NHTSA – Summary I am submitting this formal complaint regarding repeated mechanical and electrical failures involving my 2017 Toyota Highlander, purchased as a Toyota Gold-Certified vehicle with an extended Platinum Warranty. Despite strictly following Toyota’s maintenance guidelines and using only certified dealerships for all services, the vehicle has become inoperable multiple times, requiring five separate tows and resulting in repair costs exceeding $10,000. In June 2025, a Toyota dealership replaced the engine after diagnosing a warped head due to water pump failure. Following this, the vehicle began experiencing repeated charging system failures and electrical malfunctions. Multiple components—including the alternator, battery, and sensors—were replaced at another Toyota dealership based on ongoing issues, but the problems persisted. On September 2, 2025, a Toyota technician identified a missing ground wire nut as the likely root cause of these electrical failures. He confirmed the issue originated during the engine installation and that the unsecured ground caused system malfunctions. After repairs, the vehicle was again returned with a loud engine knocking noise, later traced to an improperly secured component from a prior repair. These events have raised significant concerns for the safety of myself and my family. Improper installation of major components and misdiagnosis by certified service providers have led to hazardous driving conditions, unexpected vehicle shutdowns, and unnecessary costs. I am requesting that the National Highway Traffic Safety Administration investigate this matter for potential safety defects related to improper engine installation, grounding failures, and faulty electrical diagnosis by certified Toyota service centers. Documentation, invoices, and repair records are available upon request. Thank you for your attention to this critical safety issue.