GMC Complaints

Engine coolant thermostat failed open. Resulting in reduced steering capabilities, and no AC.

The engine failed at 69,000 at highway speeds. GM inspected it at 30,000 and said it wouldn’t happen.

I have a 2024 gmc 6.2 original motor blew up at 39,000 miles. Got a new motor installed it blew up at 44,000. Now they are about to install the third motor after it’s already had two of the same failure. Second failure broke down on the interstate were three lanes turned into one above a hill. It was very dangerous.

The contact owns a 2021 GMC Yukon. The contact stated that while driving at 70 MPH with family members in the vehicle, the transmission independently shifted into neutral. No warning lights illuminated. The contact was able to steer the vehicle into a residential driveway, where the vehicle failed to restart. The contact requested towing services; however, the initial tow driver failed to arrive after nearly three hours, requiring the contact to call a second tow company. The vehicle was towed to a dealer, where it was diagnosed with engine failure, and it was determined that the engine needed replacement. The vehicle was not repaired, but replacement parts were ordered. The contact associated the failure with NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The contact stated that in January 2026, the vehicle was taken to the dealer for the recall repair, but the contact was informed that the vehicle had passed the recall inspection. The manufacturer was notified of the failure, and a case was opened. The manufacturer offered a 90% discount on the repair costs; however, the contact declined the offer and requested a full refund for both towing service fees. The failure mileage was approximately 151,017.

Filing as a proactive data point for the ongoing NHTSA Office of Defects Investigation Engineering Analysis (EA26005) regarding GM 6.2L L87 engine failures. Vehicle is a 2026 GMC Yukon XL AT4 equipped with the 6.2L V8 and 10-speed transmission. The vehicle currently has approximately 2,800 miles and operates perfectly with no mechanical symptoms, ticking, or loss of propulsion. As an active preventive measure against internal component contamination, early engine oil changes were performed at 700 miles and 1,700 miles by a certified franchise dealer (Alpine Buick GMC). The engine continues to use the factory-specified 0W-20 oil viscosity. A magnetic oil drain plug has been installed to monitor for premature ferrous bearing and crankshaft debris at future service intervals. This report is submitted to ensure 2026 model year data running 0W-20 oil is officially documented within the federal investigation scope.

The powertrain malfunctioned and it at the dealership for an engine replacement. The vehicle lost propulsion on a 2-lane road while passing another vehicle. It cut off completely and started to decelerate. There was no warning or indication that this would happen and was dangerous in that I was accelerating to pass another vehicle when the event occurred. I was able to safely pull into a driveway, but the vehicle would not crank as it could not detect what gear it should be in. It was towed to a GMC dealership locally who confirmed 2 days later that the engine would have to be replaced. It is under warranty and will take 3-4 weeks.

The contact owns a 2008 GMC Sierra 1500. The contact stated that while driving at approximately 30 MPH and towing a camper, the vehicle began to bounce while navigating curves. The traction control warning light illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed that the engine variable displacement lifter pins had failed. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 157,000. The VIN was unavailable.

While driving on a public road, the vehicle suddenly shut down and rebooted itself. Motive power was lost during the event. This has happened at least a dozen times during normal driving, including while transporting a child. Video of an occurrence was recorded. The vehicle is a 2025 GMC Hummer EV with approximately 10,400 miles and has been in service about eight months. This creates a serious safety risk. A sudden loss of propulsion and system reboot while moving can leave the driver unable to maintain speed or control in traffic and increases the risk of a crash. The vehicle has also had other problems that have been reported to an authorized GMC dealer: a front tire worn to the cords at low mileage, ADAS / Super Cruise and unexpected braking concerns, and water intrusion that has caused electrical failures affecting windows, locks, and mirrors. The manufacturer’s EV Concierge team has been contacted and the concerns have been documented. The mid-drive shutdown and reboot have not yet been fully diagnosed on a dealer repair order. No warning was consistent enough to prevent the shutdown events. The vehicle remains in use but parked and is available for inspection. Dealer and manufacturer have been made aware of the broader defect history. The shutdown condition continues to recur.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 25 MPH near the residence with the contact's daughter as a passenger, the vehicle experienced a complete loss of motive power when depressing the accelerator pedal. Several unspecified warning lights illuminated. The contact and the passenger pushed the vehicle to the residence. The vehicle was towed to an independent mechanic, where it was diagnosed that the electrical system experienced a severe power loss and the electrical modules were damaged. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 89,000.

The contact owns a 2021 GMC Sierra 1500. The contact stated that the vehicle was experiencing excessive oil consumption. The low oil level was observed, and the oil warning light illuminated. The vehicle was previously serviced at the dealer, where it was discovered that the oil was 3 quarts low at approximately 56,653 miles. The vehicle was returned to the dealer, where an oil consumption test was performed. After driving 3,000 miles, it was observed that the oil level was 2 quarts low on July 16, 2024. The dealer confirmed there was no recall coverage, and the vehicle was not repaired. The contact associated the failure with NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the dealer and manufacturer confirmed the VIN was not included. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 59,075.