GMC Complaints

On Dec 4, 2025, my wife was driving at night on a Texas road going 75mph. Her truck died while driving and the truck shifted into neutral and computer said to restart. When she did, all electrical power was lost including headlights while traveling at 75mph at night. Vehicle eventually was started after she got to the side of the road. A check engine light was present. She made it to her destination with no further problems. Vehicle was taken to the dealership the next day. They said that she may have catastrophic engine failure that is common on the 6.2 liter GM motors.

The 2025 GMC Sierra 2500 HD, equipped with the 10-speed "Allison" transmission, rough shifting,

Shift to park message has appeared again and the engine will not cut off. First happened in Feb 2020, mileage was 31,143. Took to Dealer and new wiring harness was installed. Had to take back to dealer April 2020 for same problem; shifter assembly was replaced at that time. Shift to park message came back on August 2023. Took back to Dealer and shifter harness replaced again and jumper harness was installed. Mileage was 52,993. Shift to park message has once again appeared, December 2025. Having to put car in park and push engine on/off button numerous times before engine will finally shut off.....sometimes having to unhook battery in order to kill the engine. This will be the fourth time we have had the same recurring issue repaired. My husband read through over half the 352 registered complaints and at least three fourths of them were all about the SHIFT TO PARK problem! As a female, I don't feel safe driving my Acadia not knowing if the engine will cut off or if it's actually in park or if the car will roll. Why can't GM fix this issue!!!!!! They should definitely be held accountable instead of ignoring the complaints!

Upon exiting the freeway, I pressed the gas and the vehicles rpm’s went up to 4K plus on a diesel engine, no acceleration. Thought maybe there was ice and had lost traction, tried again, same thing. Then a shudder, bang and pop. The check engine light went on and informed me of limited power and acceleration. There was no acceleration. Rpm’s would go to 2000 plus just to move. Got it to the dealership and parked it. Made a service appointment. They tried to put it into reverse and it wouldn’t move.

The GMC Sierra 1500 started a knocking sound. The collapsed lifter on a AFM cylinder bent a push rod which led to cam failure. Metal fragments are throughout the oil system.

I have been having issues with shift to park message for a yr now and it just gets worse and do not have the funds to pay for it myself bu5 see that it is a recall and gm is covering cost for other makes models of my same yr for same issue takes sometimes 20 minutes to mess with my shifter until I can finally park my car where it shuts completely off. This is a safety risk as 1 it could roll away if it isn't 2 my car could drain and die leaving me stranded by not turning off fully one time. This is ridiculous I called gm and all they just pushed me off I don't understand how this is not being taken serious especially knowing this is a known problem!

The contact owned a 2020 GMC Sierra 1500. The contact stated that after the vehicle was purchased and while driving at an undisclosed speed, the check engine warning light illuminated. The dealer was contacted. However, the check engine light turned off, and the dealer refused to inspect the vehicle. The contact stated that while driving at an undisclosed speed, the vehicle jerked and the check engine light illuminated. The dealer was contacted. However, the warranty had expired, and the dealer refused to inspect the vehicle. The manufacturer was contacted, and the contact was offered a five-hundred-dollar coupon. The vehicle was taken back to the dealer. However, no cause for the failure was found. The contact stated that an unknown part was replaced. The contact stated that the failure persisted. The contact stated that while turning on the engine, the contact's sister informed him that smoke was emitting from under the hood. The contact turned off the engine, opened the hood, and noticed that all of the wires were melted. The contact splashed water on the wires. The contact checked underneath the vehicle and noticed that the plastic that was burnt was leaking residue. The vehicle was left at the residence where the contact's mother lives. The next day, the contact noticed that the front windshield had shattered due to the heat from the burnt wires. The insurance company was notified and referred the caller to take the vehicle to be inspected. The vehicle was towed to a collision center. The contact was informed that the vehicle had a factory defect. The vehicle was not repaired. The manufacturer was notified of the failure. However, no assistance was provided since the warranty had expired.  The failure mileage was approximately 32,000.

Car rolls after parking brake is set. This happens on low hill grade and high hill grade parking location.

The contact owns a 2025 GMC Sierra 1500. The contact stated that while driving 75 MPH with the cruise control activated, the vehicle failed to accelerate as intended while depressing the accelerator pedal, and the vehicle decelerated to 10 MPH. In addition, the vehicle came to an abrupt stop independently. The contact’s upper body almost struck the front windshield. There was no warning light illuminated. The contact stated that shortly afterwards, the vehicle resumed driving normally at 75 MPH; however, the failure reoccurred after a short distance. The vehicle failed to accelerate as intended while depressing the accelerator pedal and abruptly came to a stop. The vehicle then resumed driving normally. No warning lights were illuminated. The contact arrived at the residence, and the vehicle was towed to the dealer. The vehicle remained at the dealer awaiting a diagnostic test. The manufacturer was not made aware of the failure. The approximate failure mileage was 7,800.

Vehicle experiences a failure to the Lane Departure Warning and Intellibeam headlamps functions, primarily at night. Trouble first began on 3/12/2023 and has been to two GM dealerships for 11 repairs and the problem is still unresolved. GM Executive Escalations have been opened and the problem is still unresolved. Their response is that 18 vehicles experienced this problem and the resolution was to clean the front windshield and update the camera software. This truck has had the camera replaced and software updated three times by two different dealerships. GM is now stating they are unwilling to resolve the problem any further and they would no longer send any Field Engineers to investigate the problem. I have numerous photos, videos and repair logs from with the problem and resolutions performed. Nature of problem: At night, the indicator button for selecting the Lane Departure Warning will go out. If the button is depressed, a message in the DIC indicates Lane Departure Warning Unavailable and there is no way to activate the LDW. It also causes the Intellibeam headlamps to not work. Any help you can provide is greatly appreciated.