Transmission Control Valve Recall Affects Nearly 500,000 GMC, Cadillac and Chevrolet Vehicles

Federal highway safety officials have announced a recall impacting 461,839 General Motors LLC (GM) vehicles, due to a defective transmission control valve that may cause the rear wheels to lock up, increasing the risk of an auto accident.

The transmission control valve is a critical component that regulates hydraulic fluid within the transmission, ensuring the vehicle shifts smoothly between gears. Damaged transmission control valves may gradually lose pressure within the valve, causing harsh shifting and a risk that the rear wheels will lock up.

If the rear wheels lock up while driving, the vehicle may lose stability and control, potentially resulting in accident, property damage, injury or death.

The U.S. National Highway Traffic Safety Administration (NHTSA) announced the GM transmission control valve recall on November 12, warning that certain GMC, Cadillac and Chevrolet diesel vehicles from model years 2020 through 2022 may be equipped with faulty transmission control valves that are more susceptible to excess wear over time.

The NHTSA report indicates that GM has received 1,888 field reports involving problems where rear wheels on the recalled vehicles locked up due to a faulty transmission control valve.

Additionally, the automaker has identified at least 11 incidents where vehicles veered off the road and caused property damage, as well as three reports involving minor injuries that were not associated with a collision.

The recall impacts the following diesel engine vehicles:

• 2021 Cadillac Escalade and Escalade ESV
• 2020-2022 Chevrolet Silverado 1500, 2500 and 3500
• 2021 Chevrolet Suburban
• 2021 Chevrolet Tahoe
• 2020-2022 GMC Sierra 1500, 2500 and 3500
• 2021 GMC Yukon and Yukon XL

GM first became aware of the transmission control valve problems in June, after receiving a report from a GM engineer about a customer complaint that the wheels on their vehicle locked up while towing a trailer, resulting in damage to the vehicle and trailer. The manufacturer began an investigation the following month.

The company had previously investigated this condition and determined the resulting wheel lock-up was not severe enough to cause a loss of vehicle control. However, following a reinvestigation and the compilation of new reports, GM’s Safety Field Action Decision Authority (SFADA) decided to conduct a safety recall on October 17.

GM Transmission Recall Remedy

Prior to the wheels locking up, drivers may notice changes in gear shifting and are advised to watch for harsh shifting.

Customers will begin receiving notification letters on December 9, advising them to take their vehicle to an authorized dealer, where new transmission control module software will be installed free of charge to monitor valve performance.

The new software will detect excess wear approximately 10,000 miles before a wheel lock up might occur. Once detected, the service engine light and propulsion message will display on the instrument panel and the transmission will be limited to fifth gear, preventing the possibility of the wheels locking up.

GM will provide a coverage program for faulty transmissions that are identified when the remedy software determines there is a defective control valve.

GM’s number for this recall is N242454440. Owners can contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020.

Owners can also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.