GMC Complaints

While operating the vehicle, I began to hear a metallic grinding noise originating from the center of the engine compartment. The sound was clearly audible within the cabin. Approximately one mile before the vehicle ultimately failed, the engine began to malfunction. As I slowed to a stoplight, the vehicle started to shake before shutting off abruptly and entering a coasting state. All electrical systems powered down and the vehicle would not restart. Shortly thereafter, heavy smoke began to emit both inside and outside the cabin, visibly coming from the hood and through the air vents. There was also a distinct burning odor. I attempted to restart the vehicle multiple times without success. The dashboard displayed the message: “conditions not suitable to shift.” Due to the vehicle becoming disabled on a curve and posing a safety hazard, I contacted the Sheriff’s Office for assistance to prevent a potential collision. Upon their arrival, it was noted that the engine compartment and hood area were exceptionally hot, particularly where the smoke was originating. The dealership has since confirmed they have also been unable to restart the vehicle. The vehicle has been inspected by the GMC dealer and is currently pending further evaluation by a GM-certified mechanic to determine the root cause. Prior to this incident, there were no warning lights, system messages, or other noticeable symptoms indicating an issue.

My car has started stalling and dying when i slow down, take off or when idling. No power when accelerated, and the smell of exhaust comes into my car. I was making a turn from a red light and my car spit, sputtered, and died right in the middle of the busy intersection. I was almost hit from the rear and another car had to go into on coming traffic to avoid T boning me. I took it to 2 different places to get a diagnosis reading and both places said it was a catalyst problem, and I was told that there was a recall about that because of engine oil clogging it up. My car has been using more oil than usual here lately and im guessing thats why. Now, im afraid to drive anywhere because I don't feel like it safe and the fact that my car doesn't run good enough to drive. I was told by more than 1 person that knows mechanics, that its a issue with the catalyst and that it had a recall on it but I never received one. This is a very concerning safety issue, and one that needs immediate attention before someone gets badly hurt (or worse) because of a bad car part . My car is literally just a lawn ornament now until I can get this issue resolved. I need my car to make a living and support my family. PLEASE, get the recall letters out and get this fixed before someone loses a life.

Incident description: On three occasion I have had the same catastrophic Engine failure putting myself and my family along with the general public in harms way. Starting March of 2022 while driving at approximately 60 MPH on the West Shore Expressway my truck experienced a sudden and total loss of motor power. My engine stalled out and I lost my ability to safety steer and stop my vehicle. This all happened during rush hour while driving in the left lane of traffic. This sudden loss of power forced me to maneuver the vehicle to the right shoulder of the expressway across the right lane of traffic. As there was no shoulder to pull over on the left side of the highway. This created an immediate crash risk for myself and other drivers. Upon inspection at the authorized GMC dealership where I purchased the truck new, a certified mechanic determined that the engine experienced a complete failure requiring replacement or rebuilding of the engine. I paid to have the engine rebuilt at the dealership. The second instance was similar to the above incident. Once again I paid for the repair. The third instance was more dangerous as when my trucks engine failed it almost caused an accident. As of today my truck is still sitting in the dealership for over 6 months and no one from the dealership or manufacturer will give me an answer on what has to be done now. This patter of sudden repeated engine failure clearly indicates a systemic safety defect that extends beyond normal wear and tear. I urge the NHTSA to open a defect investigation into the 2018 GMC Sierra 1500 engine systems.

I have had 2 different instances where my vehicle stops in the middle of a busy intersection or traffic and have no warning what so ever. Vehicle just shuts off and I am not able to turn back on to move out of the way. First time I got it repaired it was related to the fuel pump and now I am waiting to hear back from my mechanic to see what the issue is but so far it is an indication of the fuel pump as well. Both times I required help from law enforcement because vehicle shut off in the middle of the road and safety to myself and other drivers was an issue until tow truck arrived to move my vehicle.

Completed the oil change requirement in the recall for the 6.2L but engine blew while driving on I-10 while doing 75mph. 50k miles. Completely left stranded on major highway with family in car and vehicle flying by. GM needs to be held accountable. Their fix is not a fix.

Fire started under passenger side front seat dashboard when rear defrost was turned on.

The contact owns a 2019 GMC Sierra 1500. The contact stated that the trailer lights flashed intermittently while the vehicle is turned off. Additionally, the contact stated while driving with a trailer hitched to the vehicle, the messages "Trailer Disconnected" and "Trailer Connected" were intermittently displayed, and the running and marking lights were inoperative. The contact related the failure to GM TSB Numbers: 20-NA-198 (Trailer Running Lights Shut Off Due to Excessive Load on the Running Lamp Circuit), PIT5747B (Diagnostic Tip - Trailer Lighting Complaints with Trailering App RPO U1D) and N192213550 (Service UpdateTrailer Integration Module Software Error). The vehicle was taken to an independent mechanic, where it was determined that the failures were due to a wiring or software failure. The contact was informed that the failure was a factory defect because the fuses were in good condition. The vehicle was not repaired. The dealer and the manufacturer were not contacted yet. The failure mileage was approximately 64,000.

The contact owns a 2021 GMC Yukon. The contact stated that while driving at an undisclosed speed, the vehicle would independently activate Limp mode and would not accelerate past 30 MPH. In addition, the vehicle would not shift into the Reverse gear as intended. The vehicle was taken to a local dealer, where it was diagnosed with error codes: P0777 and P18A1. The vehicle was not repaired due to parts being on backorder. Upon further investigation, the contact related the failure to an Unknown NHTSA Campaign; however, the VIN was not included. The manufacturer was made aware of the failure. The failure mileage was approximately 90,000.

On May 27, 2026 at around 7:30pm my 2018 GMC Yukon XL Denali engined failed. I was exiting E-470 southwest bound at Gartrell Road in Aurora and the engine started knocking loudly and completely quit. As I rolled to a stop I correctly suspected that the engine seized. It would not turn over, a bad odor was present, and smoke was coming from the top of the motor. It was hard to tell exactly from where because of high wind. All belts looked fine and the Castle Rock GMC dealer I had it towed to later confirmed that the engine is seized. Fortunately I was approaching the stop light and not towing anything so the safety risk from loss of power steering and power brakes was lower than normal highway driving speeds a few seconds earlier.

Passenger brake Led Circuit board prematurely failed resulting in the entire assembly needing replacement. The assembly is $500 and higher. This is a safety issue and though there was a class action lawsuit, the light fails after 72000 miles which appears to be when GMC wont replace the part. $500 for a tail light replacement is a financial burden to be able to keep the car on the road. There is no warning when the light fails. Please consider a recall on the tail lights.