General Motors (NYSE: GM) is recalling ~62,468 model year 2019-2024 Chevrolet Silverado Medium Duty 4500HD, 5500HD, and 6500HD trucks. The brake pressure sensor assembly may leak brake fluid into the brake pressure switch and cause a short circuit, which can cause a fire. Until the recall fix is performed, owners are advised to park their vehicles outdoors. This safety defect may show with a “service brake system” malfunction indicator lamp.
“If brake fluid shorts the brake pressure switch and the associated fuse, the circuit can generate excessive heat that could result in a fire, increasing the risk of injury. An underhood fire may occur when the vehicle is off and possibly unattended,” GM told the National Highway Traffic Safety Administration in the mandatory recall filing made public by NHTSA this morning.
“Owners are advised to park outside and away from structures until the recall repair is complete.” Dealers will replace the brake pressure switch wire harness, free of charge as required by U.S. federal safety regulations. Interim letters notifying owners of the safety risk are not expected to be mailed until 28 July 2025. Second letters will be mailed once the repair for the safety defect is available.
Owners may contact GM customer assistance number at 1-866-467-9700. GM’s number for this recall is N242482680. Vehicles in this recall that were previously repaired under NHTSA 23V266 or 23V-266 will need to have the new defect remedy completed. Again, owners are advised to park outside and away from structures until the recall repair is complete. Second letters will be mailed once the remedy is available.
Owners may contact GM customer assistance number at 1-866-467-9700. GM’s number for this recall is N242482680. Vehicles in this recall that were previously repaired under 23V266 will need to have the new remedy completed. Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 or go to www.nhtsa.gov about NHTSA recall 25V390 or 25V-390.
Chronology
- On 13 April 2023, GM issued NHTSA Recall 23V-266 to address a condition in which zinc sealant in the subject vehicles’ brake pressure sensors could fragment and interfere with a diaphragm intended to prevent brake fluid from leaking into the sensor wiring harness. A short circuit caused by leaking fluid could activate the brake assist pump when the brake is not applied and, in rare conditions, generate excessive heat that could result in an under-hood fire.
- On 11 October 2024, a GM brand quality manager submitted an issue to GM’s Speak Up For Safety (SUFS) program based on a field report of a 2023 Silverado Medium Duty truck that was exhibiting unintended brake pump activation and was not part of the 23V266 or 23V-266 recall population. That vehicle had been built with an improved brake pressure sensor design intended to eliminate the zinc-sealant fragmentation issue.
- On 24 November 2024, GM opened a product investigation after analysis found brake fluid in the sensor wiring harness.
- On 18 December 2024, GM received another potentially related field report involving a 2021 Silverado Medium Duty truck that had already been repaired under recall 23V-266. GM’s examination of the sensor in January 2025 identified evidence of brake fluid in the wiring harness. On January 16, 2025,GM completed testing of three warranty-returned parts from other vehicles that were not included in the 23V266 population, each confirming brake fluid present in the harness.
- On 3 March 2025, GM and International Motors, the manufacturer of the subject vehicles, contracted with Akron Rubber Development Lab (ARDL) to test the material properties of the diaphragm seal. Testing completed on 24 April 2025 determined that the diaphragm was degrading due to the supplier’s [ Kodiak Controls, Romeoville IL – AutoCrat] use of an unauthorized chemical in the rubber that reacted with the brake fluid.
- On April 30, 2025, GM’s investigator retrieved updated field data, identifying one alleged fire among 160 potentially related reports.
- GM inspected the vehicle on 28 May and concluded that the incident was likely related to the subject condition. GM received notice of the field incidents between 14 November 2024 and 30 April 2025. GM is not aware of any accidents or injuries associated with this condition.
- On 5 June 2025, GM’s Safety Field Action Decision Authority (SFADA) decided to conduct a safety recall. This recall is related to NHTSA recall 23V266. “It is based on the discovery of another root cause that can create the same condition that was the subject of the earlier recalls.”
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.
GM Fire Recall – Chevrolet Silverado Medium Duty Trucks
General Motors (NYSE: GM) is recalling ~62,468 model year 2019-2024 Chevrolet Silverado Medium Duty 4500HD, 5500HD, and 6500HD trucks. The brake pressure sensor assembly may leak brake fluid into the brake pressure switch and cause a short circuit, which can cause a fire. Until the recall fix is performed, owners are advised to park their vehicles outdoors. This safety defect may show with a “service brake system” malfunction indicator lamp.
“If brake fluid shorts the brake pressure switch and the associated fuse, the circuit can generate excessive heat that could result in a fire, increasing the risk of injury. An underhood fire may occur when the vehicle is off and possibly unattended,” GM told the National Highway Traffic Safety Administration in the mandatory recall filing made public by NHTSA this morning.
“Owners are advised to park outside and away from structures until the recall repair is complete.” Dealers will replace the brake pressure switch wire harness, free of charge as required by U.S. federal safety regulations. Interim letters notifying owners of the safety risk are not expected to be mailed until 28 July 2025. Second letters will be mailed once the repair for the safety defect is available.
Owners may contact GM customer assistance number at 1-866-467-9700. GM’s number for this recall is N242482680. Vehicles in this recall that were previously repaired under NHTSA 23V266 or 23V-266 will need to have the new defect remedy completed. Again, owners are advised to park outside and away from structures until the recall repair is complete. Second letters will be mailed once the remedy is available.
Owners may contact GM customer assistance number at 1-866-467-9700. GM’s number for this recall is N242482680. Vehicles in this recall that were previously repaired under 23V266 will need to have the new remedy completed. Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 or go to www.nhtsa.gov about NHTSA recall 25V390 or 25V-390.
Chronology
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.