GMC Complaints

Lifter failure with cylinder #6. Car violently shook prior to this failure. No engine lights or messages until the next day when tried to drive. Ended up towing car to dealer. Car had 76k miles on it. Recall on 6.2L, but not on the 5.3L which is not immune to this same issue as the 6.2L engine.

Component/system malfunctioned: Adaptive Cruise Control integrated with Traffic Sign Recognition/Speed Limit Assist (camera-based speed sign detection and automatic speed adjustment). Vehicle available for inspection upon request. While driving ~35 mph in 35 mph zones with Adaptive Cruise Control engaged, the system repeatedly misread speed signs (or GPS data) as much higher (e.g., 75 mph). The vehicle then automatically accelerated aggressively toward the incorrect higher speed without driver accelerator input. Acceleration is sudden and strong due to electric powertrain torque. This problem can be reproduced in multiple locations in low-speed zones. Safety risk: Vehicle sped up dangerously in restricted areas (residential, traffic, pedestrians), risking loss of control or collision before I could brake or disengage system. No crash/injury occurred, but risk was high. Problem not reproduced/confirmed by dealer or service center. Vehicle/component not inspected by manufacturer, police, insurance, or others. No warning lamps/messages/symptoms before acceleration; dashboard briefly showed incorrect higher limit. First occurrence UNKNOWN, but multiple incidents since ownership. Appears to be defect in software, camera recognition, or integration of Traffic Sign Recognition with Adaptive Cruise Control, causing unintended high-speed acceleration in low-speed areas.

My 2026 GMC 1500 is equipped with the 2.7L L3B & 8L90 Transmission. At approximately 1000 miles, I noticed that in 2nd between 2700-3200 RPM, a vibration could be felt throughout the cabin and would occur whether with or without throttle application. I am able to recreate the issue during hard acceleration or placing in manual mode. No matter the Vehicle mode selection (sport, normal, snow, tow/haul, etc.), the issue still persists. I took the vehicle to a local GMC dealer at approximately 6K miles to diagnose. I requested that we test drive another 1500 with the same 2.7L and Transmission. They brought out a 2026 Elevation Quad Cab with the 2.7L; less than 20 miles on the odometer.The same vibration was present in 2nd gear at same RPM band. I requested that the issue be escalated to a local GM rep. for further investigation. However the response from the dealer was inadequate and basically stated that no warranty work would be considered because it seems to be “normal operation”.

I bought my truck on 10/29/25 on 12/04/25 haven’t even maid my first payment on the truck yet and my wife was on her way to work at 4 am when the engine shut off on its own and went in to neutral. She tried starting the truck again and it wouldn’t so she had to leave the truck abandoned in the middle of the road and walk to work in the cold and dark. We ended up getting the truck towed home a few hours later when there was a tow truck available. I work out of town so on 12/07/24 when I got back in town I started the truck up and everything seemed normal so I took it for a spin and right as I was getting on the highway it lost propulsion, engine shut off, and truck shifted on its own to neutral. I was almost rear ended by the truck behind me luckily I was able to get the truck out of the way in time. I had to sit and wait for 3 hours until a tow truck was able to tow the truck. This was on a Sunday so I could not get it dropped off at the dealership due to them being closed until the next day! Finally I got it towed to the dealer (all tow’s paid out of pocket as well)… 3 days later the dealer calls me back to let me know I’m getting a new engine not sure how long it will take, but they will get me a rental mean while and that’s all.

The vehicle shifted into Neutral while driving, locked out gear selection, triggered a transmission warning, and now will not restart.

Radiator is leaking where plastic meets metal. Leaking coolant at upper corner driver side. This is crazy for a 70k truck. It is a known problem. Dealer refused to submit a claim to GM. I am seeing people get theses replaced. It has been an issue since coolant control Valve was replaced.

TRAVELING ON INTERSTATE GOING AT THE POSTED SPEED LIMIT AND TURNED OFF THE INTERSTATE ONTO MY EXIT TURN AND VEHICLE ENGINE STARTED KNOCKING AND ENGINE SHUT OFF OIL WARNING LIGHT CAME ON ALL WHILE TRYING TO STOP THE VEHICLE AT THE CROSS TRAFFICE STOP SIGHN AND ENDED UP STOPPED IN THE MIDDLE OF ANOTHER HIGHWAY BARLEY MISSING THE CROSS TRAFFIC COMING AT ME FROM BOTH DIRECTIONS. THIS HAPPENED AT I94 AND COUNTY HIGHWAY 34 AT BARNESVILLE MINNESOTA EXIT. THIS SUDDEN ENGINE FAILURE NEARLY KILLED ME AND THE 2 VEHICLE DRIVERS THAT NEARLY STRUCK MY TRUCK FROM BOTH DIRECTIONS. GMC WOULD NOT HELP ME WITH MY REPAIR OF OVER $11000.00 DOLLARS FOR A NEW CRATE MOTOR FROM GMC. SITING MY TRUCK DID NOT FALL UNDER THE L87 RECALL. FAILURE ROD BEARINGS AND CRANK BEARINGS WITH A TON METAL SHAVINGS IN THE OIL AND FILTER. NO WARNING THIS WAS GOING TO HAPPEN. MY TRUCK HAD 95000 MILES ON IT WHEN IT NEARLY KILLED ME AND OTHERS. INDEPENDENT SERVICE CENTER JOHNSONS AUTO REPAIR IN MOORHEAD MN INSTALLED THE NEW CRATE MOTOR FROM LUTHER GMC FARGO ND.

Vehicle stalled out, lost power, left me stranded on side of road. No warning, check engine lights or any other inclination prior. Turn out to be fuel pump control module.

Tailgate opened on its own while driving, creating a safety hazard where items inside could have fallen out. The tailgate was secured prior to driving.

The vehicle drove fine had no warning/ check engine lights. My girlfriend came up to a busy intersection and when she proceeded to cross the intersection the vehicles motor locked up stopping the vehicle in the middle of the intersection with traffic coming from both north and south direction. We had poor visibility due to blowing snow so she had to bail from the vehicle and stand on the side of the road so she would not be harmed if the vehicle was t boned. Vehicle stopped so hard and fast it threw her into the steering wheel. Was unable to get the vehicle restarted and could not get it to shift into neutral so vehicle blocked 1 lane of traffic completely and half of another lane until tow truck arrived to remove from road.