General Motors has issued a recall for 461,839 pickup trucks and SUVs that are equipped with diesel engines due to a potential transmission issue that could lead to rear-wheel lockup. The National Highway Traffic Safety Administration (NHTSA) has identified a transmission control valve in the affected vehicles that may experience excess wear over time. This wear could result in a loss of pressure within the valve, which controls the flow of hydraulic fluid responsible for gear shifts and connecting the engine to the driven wheels.
The NHTSA has warned that a pressure loss in the valve could cause harsh shifting or, in rare cases, momentary rear-wheel lockup. This lockup occurs when the vehicles’ 10-speed automatic transmissions downshift from eighth gear to fifth gear. General Motors has reported 11 incidents potentially related to this defect, with some cases resulting in trucks veering off roadways and causing minor property damage. While three minor injuries were reported, none were associated with collisions.
The affected vehicles, if equipped with diesel engines, include the 2021 Cadillac Escalade and Escalade ESV, Chevrolet Tahoe, Suburban, Silverado 1500, 2500, and 3500, as well as the GMC Sierra 1500, 2500, and 3500, and the 2021 GMC Yukon and Yukon XL. General Motors will address this issue by installing new transmission-control software that can monitor valve performance and detect excess wear. If excessive wear is detected, the software will limit the transmission to fifth gear to prevent wheel lockup, although this may result in sluggish acceleration.
Dealers will install the software at no cost to customers, and General Motors will reimburse those who have already paid for repairs related to this issue. Owner notification letters will be sent out on December 9, and affected owners can contact GM customer service at 1-888-988-7267 or visit GM’s recall page and reference recall number N242454440 for more information. Additionally, customers can reach out to the customer service lines for Cadillac, Chevy, and GMC at 1-800-458-8006, 1-800-222-1020, and 1-800-462-8782, respectively, for assistance.
