General Motors (NYSE: GM) is recalling ~1100 model-year 2020 Chevrolet Silverado 2500 and 3500, GMC Sierra 2500 and 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 pickups with diesel engines that may have been repaired incorrectly with the wrong software under NHTSA recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up. (Read AutoInformed.com on GM Recall for Wheel Lockup on Diesel Pickups and SUVs)
“Dealers were presented with an option in GM’s Global Warranty Management (GWM) system to mark a vehicle as having been remedied without first verifying the most recent software version was available. That option has been removed,” GM said in the required safety defect recall filing made public by the National Highway Traffic Safety Administration (NHTSA) this morning.
“This recall only involves vehicles equipped with diesel engines that were recalled under 24V797. Vehicles equipped with gas engines use a different transmission and are not affected by this recall,” GM said.
“As part of the remedy under NHTSA Recall No. 24V797, dealers were instructed to install new transmission control module (TCM) software that will monitor valve performance and detect excessive wear approximately 10,000 miles before a wheel lock up condition could occur. In some of the vehicles repaired under that recall, dealers installed an incorrect software version. Vehicles that received the correct software update under 24V797 are not affected by this recall,” GM said.
Chronology
- On 9 September 2025 – GM opened a product investigation to evaluate whether an issue discovered in its Global Field Action Management (GFAM) system may have permitted dealers to install incorrect software versions as part of prior field action remedies.
- Between September 2025 and December 2025 – the investigation involved an in-depth review of 56 previously launched recalls. During this period, no evidence was found to indicate that any vehicles had been released into the field with an incorrect software version as a result of the identified issue.
- On 19 January 2026 – the investigator discovered that some vehicles subject to NHTSA Recall No. 24V797 may have been affected due to a previously unknown delay in the software rollout breakpoint for that recall. These 1055 vehicles were remedied during a six-day period from 2 December 2024 to 8 December 8 2024. The remaining 462,240 vehicles subject to the recall were not affected.
- On 5 February 2026 – GM’s Safety Field Action Decision Authority (SFADA) decided to conduct a safety recall. Dealers were notified on 12 February 2026.
Owner notification of an available remedy is estimated to start mailing on 30 March 2026.
Dealers will inspect the vehicles to determine whether the incorrect software update was installed and, if necessary, perform an additional software update. The new transmission control software will detect this condition and prevent rear wheel lock-up by placing the transmission into fifth gear until the next key cycle. This will be accompanied by a service engine light and reduced propulsion message. The driver will experience this as sluggish or reduced propulsion.
About Ken Zino
Ken Zino, editor and publisher of AutoInformed, is a versatile auto industry participant with global experience spanning decades in print and broadcast journalism, as well as social media. He has automobile testing, marketing, public relations and communications experience. He is past president of The International Motor Press Assn, the Detroit Press Club, founding member and first President of the Automotive Press Assn. He is a member of APA, IMPA and the Midwest Automotive Press Assn.
He also brings an historical perspective while citing their contemporary relevance of the work of legendary auto writers such as Ken Purdy, Jim Dunne or Jerry Flint, or writers such as Red Smith, Mark Twain, Thomas Jefferson – all to bring perspective to a chaotic automotive universe.
Above all, decades after he first drove a car, Zino still revels in the sound of the exhaust as the throttle is blipped during a downshift and the driver’s rush that occurs when the entry, apex and exit points of a turn are smoothly and swiftly crossed. It’s the beginning of a perfect lap.
AutoInformed has an editorial philosophy that loves transportation machines of all kinds while promoting critical thinking about the future use of cars and trucks.
Zino builds AutoInformed from his background in automotive journalism starting at Hearst Publishing in New York City on Motor and MotorTech Magazines and car testing where he reviewed hundreds of vehicles in his decade-long stint as the Detroit Bureau Chief of Road & Track magazine. Zino has also worked in Europe, and Asia – now the largest automotive market in the world with China at its center.
Rear-Wheel Lockup Recall on 2020-22 GM Diesel Pickups
General Motors (NYSE: GM) is recalling ~1100 model-year 2020 Chevrolet Silverado 2500 and 3500, GMC Sierra 2500 and 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 pickups with diesel engines that may have been repaired incorrectly with the wrong software under NHTSA recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up. (Read AutoInformed.com on GM Recall for Wheel Lockup on Diesel Pickups and SUVs)
“Dealers were presented with an option in GM’s Global Warranty Management (GWM) system to mark a vehicle as having been remedied without first verifying the most recent software version was available. That option has been removed,” GM said in the required safety defect recall filing made public by the National Highway Traffic Safety Administration (NHTSA) this morning.
“This recall only involves vehicles equipped with diesel engines that were recalled under 24V797. Vehicles equipped with gas engines use a different transmission and are not affected by this recall,” GM said.
“As part of the remedy under NHTSA Recall No. 24V797, dealers were instructed to install new transmission control module (TCM) software that will monitor valve performance and detect excessive wear approximately 10,000 miles before a wheel lock up condition could occur. In some of the vehicles repaired under that recall, dealers installed an incorrect software version. Vehicles that received the correct software update under 24V797 are not affected by this recall,” GM said.
Chronology
Owner notification of an available remedy is estimated to start mailing on 30 March 2026.
Dealers will inspect the vehicles to determine whether the incorrect software update was installed and, if necessary, perform an additional software update. The new transmission control software will detect this condition and prevent rear wheel lock-up by placing the transmission into fifth gear until the next key cycle. This will be accompanied by a service engine light and reduced propulsion message. The driver will experience this as sluggish or reduced propulsion.
About Ken Zino
Ken Zino, editor and publisher of AutoInformed, is a versatile auto industry participant with global experience spanning decades in print and broadcast journalism, as well as social media. He has automobile testing, marketing, public relations and communications experience. He is past president of The International Motor Press Assn, the Detroit Press Club, founding member and first President of the Automotive Press Assn. He is a member of APA, IMPA and the Midwest Automotive Press Assn. He also brings an historical perspective while citing their contemporary relevance of the work of legendary auto writers such as Ken Purdy, Jim Dunne or Jerry Flint, or writers such as Red Smith, Mark Twain, Thomas Jefferson – all to bring perspective to a chaotic automotive universe. Above all, decades after he first drove a car, Zino still revels in the sound of the exhaust as the throttle is blipped during a downshift and the driver’s rush that occurs when the entry, apex and exit points of a turn are smoothly and swiftly crossed. It’s the beginning of a perfect lap. AutoInformed has an editorial philosophy that loves transportation machines of all kinds while promoting critical thinking about the future use of cars and trucks. Zino builds AutoInformed from his background in automotive journalism starting at Hearst Publishing in New York City on Motor and MotorTech Magazines and car testing where he reviewed hundreds of vehicles in his decade-long stint as the Detroit Bureau Chief of Road & Track magazine. Zino has also worked in Europe, and Asia – now the largest automotive market in the world with China at its center.