Toyota, Lexus UA80 Transmission, Torque Converter Problems Caused by Defects, Class Action Lawsuit Says

A proposed class action lawsuit claims that certain newer Toyota and Lexus vehicles are equipped with UA80 eight-speed transmissions plagued by mechanical and software defects, significant issues that the automaker has allegedly attempted to hide from consumers.

The 31-page Toyota lawsuit contends that a handful of vehicle models made by the auto manufacturer are equipped with transmissions hampered by a “design flaw” that can cause excess heat to build up inside the transmission, which can then cause it to burn transmission fluid. This can lead to premature wear, stalling events and ultimately transmission failure, among “other dangerous situations” for drivers, the class action lawsuit emphasizes.

According to the suit, the transmissions in the Toyota and Lexus models at issue are also plagued by equally defective software that can cause premature upshifts and torque-converter clutch engagements, all of which can cause a transmission to degrade “faster than expected.”

The complaint says that the UA80 transmission problems have “been known to be an issue for several years,” and alleges that Toyota has actively concealed from drivers that the transmissions and their related software were faulty. As a result, consumers have incurred diminished vehicle values, unexpected—and costly—repair expenses, and limits on the safety and reliability of their vehicles, the filing contends, alleging that Toyota has failed and/or refused to remedy the issues at no expense, even for vehicles under warranty, when notified by drivers.

UA80 transmission in newer Toyota, Lexus models was redesigned, suit says

According to the complaint, the Toyota and Lexus models hampered by the alleged transmission defect, known as the “class vehicles,” include:

• 2017-present Toyota Highlander;
• 2019-present Toyota RAV-4;
• 2023-present Toyota Grand Highlander;
• 2017-2024 Toyota Camry;
• 2017-2020 Toyota Sienna; 29180 Toyota Avalon;
• 2019-present Lexus ES350;
• 2022-present Lexus ES250;
• 2023-present Lexus RX350;
• 2022-present Lexus NX250;
• 2022-present Lexus NX350; and
• 2024-present Lexus TX350.

Though many of the above-listed vehicle models have been around for decades without widespread transmission problems, the case details that the particular transmission at issue, the direct-shift UA80 model, was newly designed and implemented into new vehicles starting in 2017. The reason for the redesign was Toyota’s desire to develop a new transmission that was more efficient and could reduce CO2 emissions, the complaint relays.

“As compared to previously a developed six speed transmission used by Toyota, the UA80 was designed to be 8 percent more efficient and ‘6kg lighter and 5 mm shorter than the previous 6-speed automatic transaxle,’” the case states.

According to the suit, the transmission redevelopment included, among other substantial modifications, changing the location of the valve body, from the bottom surface of the previous six-speed automatic transaxle to the front, to lower each vehicle’s center of gravity and simplifying the gear control by reducing the number of components needed to change gears.

Though presented as a net-positive adaptation, the simplified transmission changes, in reality, produced deeper mechanical and processing issues, the filing relays.

Further, the lawsuit says that a related software defect “lies with the failure of the transmission control module, engine control module, and powertrain module.” The software is faulty because it “prioritizes early upshifts and torque-converter clutch engagement” to maximize fuel economy, even though this frequent cycling creates excessive stress on the transmission due to overheating and degrading components and fluid, the complaint explains.

The complaint stresses that the alleged Toyota and Lexus transmission and software problems are dangerous and make affected vehicle models unreliable.

Both defects are inherently dangerous as a faulty transmission can cause a vehicle to act in unintended ways, as a defective transmission may not be able to engage or stay in gear, cause slipped gears, cause fluid leaks, cause delayed shifts, cause missed gear shifts, cause delayed engagement and harsh shifting, cause burning smells and unusual noises, as well as cause the vehicle to lose power.

These defects can have disastrous effects, as a defective transmission can cause a vehicle to stop mid-operation.”

Per the suit, Toyota, to date, has issued no recall for the above-listed vehicle models or offered consumers reimbursement for out-of-pocket repair costs.

Toyota has known of the UA80 transmission problems for years, lawsuit claims

According to the class action suit, Toyota has known since at least August 2016 that its UA80 transmissions were defective, with consumers reporting problems to the National Highway Traffic Safety Administration (NHTSA) since as early as 2017.

In that time, hundreds of reports from drivers have been lodged with the NHTSA and on other blogs, websites and forums, noting of “hazardous” vehicle failure, poor driving conditions, abnormal noises and smells, and an overall diminished lack of vehicle value, the case shares.

The case argues that, in light of the plethora of consumer reports and given robust industry-standard presale vehicle testing, Toyota has been aware, or should have been aware, of the transmission defect plaguing the near-dozen vehicle models listed on this page.

To date, Toyota has failed to take any “…necessary actions to adequately disclose or cure the Transmission Defect after the existence of the Transmission Defect came to the public’s attention and sat on its reasonable opportunity to cure or remedy the Transmission Defect,” the complaint says.

“Despite knowing that this defect existed, Defendants have continued to market and sell their vehicles with defective transmissions,” the class action lawsuit summarizes.

Toyota has failed to fix transmission problems under warranty, drivers claim

Per the complaint, drivers whose vehicles have manifested the transmission defect while still under the automaker’s Powertrain Limited Warranty have received little to nothing from Toyota as far as repairs and corrections. As the case tells it, many drivers who have brought their class vehicles to authorized repair centers are often told that there is nothing wrong with their vehicles.

Those who are issued recommendations are often quoted thousands of dollars in repair costs, which are seldom covered by the extremely limited warranty period, which only covers a vehicle up to five years or 60,000 miles, whichever comes first, the complaint contends.

“Defendants’ warranty disclaimers, exclusions, and limitations, to the extent that they may be argued to apply, were, at the time of sale, and continue to be, unconscionable and unenforceable to disclaim liability for a known, latent defect,” the lawsuit argues. “Defendants knew or should have known when they first made these warranties and their limitations that the Transmission Defect existed, and the warranties might expire before a reasonable consumer would notice or observe the Transmission Defect.”

Who is covered by the Toyota/Lexus transmission defect lawsuit?

The case looks to represent all individuals in the United States who are current or former owners and/or lessees of any of the class vehicle models listed on this page.

How do I join the class action lawsuit?

Typically, there is nothing a consumer needs to do to join or sign up for a class action lawsuit when it’s first filed. The time to take action typically occurs in the event of a class action settlement, at which point the people covered by the case, called class members, should receive notice of the settlement with instructions on how to claim their benefits.

If you own or lease any of the Toyota or Lexus vehicles listed on this page, or simply want to stay in the know on class action lawsuit and class action settlement news, sign up for ClassAction.org’s free weekly newsletter.

Looking for current class action lawsuits to join? Check out ClassAction.org’s list of current class action lawsuits.