GMC Complaints

Vehicle was brought in for Campaign #25V274000 (6.2liter engine failure) and passed the manufacturer's testing. The oil was changed to a heavier weight with a new filter installed. Appx 770 miles later, the engine suffered a total failure. The engine was replaced under manufacturers warranty.

I had the truck inspected for recall N25249400 on August 11, 2025 with 24,610 miles. It passed the recall inspection and the dealer changed the oil to GM recall recommended oil. On January 18, 2026 with 28,275 miles, the engine seized while on a major highway. The truck lost all power and just turned off amd would not start or turn over. The vehicle was towed by the Police due to the vehicle being in a dangerous spot in the middle of a lane on the highway whi h I had to pay out of pocket. January 19, 2026, the GM dealer confirmed that the truck needs a new engine due to the recall defect. They said that they had just ordered a new engine, but does olnot know hpw long ot will take to get and then install. The dealer is unable to provide a rental vehicle which means, I can't WORK!

Engine has developed a serious lifter / cam issue. dealer identified it as a result of Displacement on Demand design. Total engine replacement recommended by dealer but since the mileage on that vehicle is over 100,000 warranty, the repair is not covered. Known issue, should have been pointed out by dealer / manufacturer before warranty expiration. FYI _ I do all repair work at dealer. Vehicle looses power intermittently is is not drivable at any distance. Manufacturing / design issue known over different versions of this engine since 2010, I believe.

Driving along on an empty road and my panoramic sunroof back glass exploded it sounded like a gunshot going off. Could have caused a wreck it was so loud and scary.

While driving in traffic in March 2025, the vehicle experienced a sudden and complete engine failure, creating an unsafe condition. Subsequent diagnosis confirmed failure of the camshaft and lifters, requiring full engine replacement. General Motors declined to cover this repair. However, this failure is consistent with widely reported camshaft and lifter issues affecting other GMC and GM vehicles equipped with the same 6.2L engine platform. Due to the unavailability of replacement engines through GM, I was forced to wait several months for an engine sourced through Jasper Engines. During this time, the vehicle was inoperable, resulting in over $10,000 in out-of-pocket expenses, including extended rental vehicle costs. The engine replacement was completed by Camden Automotive and Diesel in Camden, South Carolina, who maintain all service and maintenance records related to this repair.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving at various speeds, there was an abnormally loud clamoring sound coming from the engine. There was no warning light illuminated. The vehicle was taken to a dealer, and the mechanic informed the contact that the engine might fail soon. The contact was able to continue driving the vehicle, but the contact was advised to bring the vehicle back if the failure worsened. The following day, the contact stated that the front of the vehicle started shaking with several unknown warning lights illuminated on the instrument panel. The vehicle was taken back to the dealer and remained with the dealer undiagnosed. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 71,000.

The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the engine seized. No warning lights were illuminated. The contact disabled the stop-to-start feature, and the failure ceased. The vehicle was taken to the dealer, and the contact was informed that the repair was not covered under recall. In addition, the contact was informed that the vehicle needed to remain with the dealer for two weeks while performing diagnostic tests on the vehicle. The contact was unable to be without a vehicle for two weeks. The vehicle was the only means of transportation. The contact stated that the failure was a known failure with the vehicle and that the manufacturer needed to repair the vehicle. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure, and a case was filed. The contact was informed that the repair was not covered under the recall. The contact was advised to take the vehicle to the dealer for a diagnostic test. The failure mileage was approximately 123,000.

When driving at slow speed and wheels turning right or left you can hear a humming coming from the suspension. Unable to identify the issue. When wheels get straight the humming goes away

The contact owns a 2018 GMC Acadia. The contact stated that while starting the vehicle and attempting to shift into park, the vehicle failed to recognize that the transmission was in park(P). There was no warning light illuminated. The contact stated that several attempts were required to shift the vehicle into park(P) to turn off the vehicle. The contact further stated that on other occasions, the vehicle remained stuck in park(P) and failed to shift into drive(D). The contact related the failure to TSB: 19-NA-205. The dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure, and a case was opened. The contact was referred to the NHTSA Hotline to report the failure. The approximate failure mileage was 120,000.

On 8/22/25 was brought to my local GMC dealer for the L87 engine propulsion recall. The dealership tested and said the vehicle passed the test. On 12/3/25 while driving on a multi lane highway the vehicle engine stopped abruptly. The message restart engine appeared on the dashboard. I had to negotiate other vehicle travelling at highway speeds to get to coast off to a side street. The transmission went into "park" and could not be shifted to neutral with a message on the dashboard "transmission cannot be shifted in this configuration". I was blocking the roadway and responding police asked that I attempt to restart the vehicle. I did this numerous times but would not start and the battery ran down. The vehicle was towed to the GMC dealer who said the battery failed and replaced it at my cost even after I told them it was fine and run down from trying to start numerous times while blocking traffic. On 12/17/25 while trying on the same highway, the engine abruptly shut off again in high speed traffic with the same message. I couldn't get fully in the shoulder dye to residual snow from plowing coasting powerless as the vehicle slowed. The transmission locked into park again and I ended up getting towed back to the GMC dealership. They advised me the engine seized up and would have to be replaced. I am still waiting to get the vehicle back