General Motors has initiated a significant recall affecting nearly 100,000 Cadillac and Chevrolet Camaro vehicles, addressing a critical issue with their ten-speed automatic transmissions. The core problem lies within the transmission's control valve, which is susceptible to excessive wear over time. This wear can lead to a gradual loss of hydraulic pressure, resulting in harsh shifting and, in severe cases, the potential for momentary wheel lock-up, posing a significant safety risk.
The impetus for this recall stemmed from a concerning incident reported in September 2024. The owner of a 2021 Cadillac CT5, an all-wheel-drive model, experienced a sudden lock-up of both front wheels while driving, causing the vehicle to shift into neutral. This alarming event resulted in substantial damage, necessitating the replacement of both the engine and the front differential. Notably, GM was already aware of the potential for this issue, having identified that "in some applications, excessive wear in a control valve … was causing harsh downshifting and, in rare cases, a momentary lock-up of the wheels." However, the automaker initially deemed this risk "not sufficient to cause a loss of vehicle control."
The real-world incident of wheel lock-up prompted a renewed investigation, which uncovered 115 field reports of alleged lock-ups, along with one reported accident. This evidence compelled GM to take decisive action and initiate a recall. The recall encompasses 90,081 vehicles, including the 2019-2020 Cadillac CT6, 2020-2021 Cadillac CT4, 2020-2021 Cadillac CT5, and 2020-2022 Chevrolet Camaro. The Chevrolet Camaro is the most affected model, with 50,147 units being recalled, nearly double the number of Cadillac CT5 vehicles.
To address the issue, GM dealers will install new transmission control module software. This software is designed to detect excessive wear approximately 10,000 miles before a potential wheel lock-up condition could occur. Upon detection, the ten-speed automatic transmission will be limited to fifth gear until the next key cycle, preventing lock-ups that typically occur during downshifts from eighth gear. In addition, the software will activate the service engine light and display a reduced propulsion message, alerting the driver to the issue.
While this software update aims to mitigate the risk of wheel lock-up, it does not constitute a complete fix. Owner notifications are scheduled to begin in April, but GM currently only has the updated software available for a limited number of vehicles, including the Cadillac CT4, CT5, and some CT6 models.
A GM spokesperson clarified that the issue of front-wheel lock-up is primarily associated with all-wheel-drive models, like the Cadillac CT5 involved in the initial incident. "Please note that in our recall defect description, we do not state 'front wheel lock up.' Rather, we say '… the wheels may experience a momentary lock up,'" the spokesperson stated. "Therefore, this rare occurrence would only be a possible issue for only rear wheels on rear-wheel drive vehicles and a possible issue for front wheels or rear wheels on all-wheel drive vehicles. The CT5 mentioned in GM’s voluntary safety recall report that experienced the momentary front-wheel lock up was an all-wheel drive vehicle."
Despite the NHTSA's initial lack of explicit distinction between all-wheel-drive and rear-wheel-drive models, it is now clear that the front-wheel lock-up risk is specific to all-wheel-drive vehicles. This clarification highlights the complexity of the issue and the importance of precise communication in safety recalls.