GMC Complaints

The contact owns a 2024 GMC Sierra 1500. The contact stated that while driving at approximately 35 MPH, he depressed the brake pedal and the vehicle accelerated independently. The contact stated he drove across four lanes of traffic and regained control of the vehicle. The contact stated that as he was slowing for a traffic signal, he again depressed the brake pedal. The contact stated that the pedal went to the floorboard, and the vehicle would not stop. The contact stated no warnings illuminated. The contact stated that his vehicle crashed into the rear end of the vehicle in front of him. The contact stated that there were scratches on his front bumper and no damage to the other vehicle. There were no injuries, and the police were not called. The contact stated that both vehicles were able to drive away. The contact had the vehicle towed to a local dealer, where it was diagnosed and determined that the master brake cylinder needed to be replaced. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 13,000.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving on several occasions at undisclosed speeds, the engine was idling low, and the vehicle hesitated like it would stall. The contact stated that while stopped at a red light on several occasions, while the accelerator pedal was depressed, the vehicle jerked and then accelerated. The contact stated that when the accelerator pedal was released, the vehicle continued to accelerate. The brake pedal was depressed to slow down the vehicle. The check engine warning light was illuminated. The vehicle was taken to a dealer, where it was diagnosed, and determined that the fuel pump module needed to be replaced. The vehicle was repaired, but the failure reoccurred a short while later. The manufacturer was notified of the failure. The failure mileage was 97,000.

The contact owns a 2024 GMC Sierra 1500. The contact stated that while coasting at speeds of approximately 1- 3 MPH, and gently pressing the accelerator, the vehicle suddenly surged forward and accelerated quickly. The accelerator pedal was released, and the brake pedal was depressed, allowing the vehicle to come to a stop. The failure had occurred approximately 5 times within a year and a half. The vehicle was not taken to the dealer to be diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 3,000.

My vehicle fuel pump control module has failed. GMC has an open recall for my year, make and model however claims that my vehicle is not listed on the recall list that came out around 9/15/2025. I contacted GMC and they cannot provide me with a specific reason as to why it’s not included.

Multiple people including my family are experiencing leaks in 2021 and newer GMC Yukons and Chevy tahoes. The back seatbelt is causing leaks, damaging the interiors. This can cause mold and health issues as well as electrical wiring issues causing accidents due to shortages occurring. Check Reddit on the number of complaints.

Ac not working properly. Ac blows air to defrost vents foging front windshield and side windows causing bad visibility

The engine coolant control valve on my 2020 GMC Sierra 1500 with the LM2 Duramax diesel failed. The failed part is still in my truck, which remains at the dealership awaiting replacement. The repair is delayed due to the part being on nationwide backorder, further highlighting that this is a widespread issue. When the valve failed, the truck entered reduced engine power mode while I was traveling on the interstate. This limited my speed to about 40 mph while climbing a hill. The sudden loss of power in high-speed traffic created a serious safety hazard, as it significantly increased my risk of being rear-ended or involved in a collision with faster-moving vehicles. I drove the truck directly to the dealership after the incident, where the problem was immediately confirmed. The issue was diagnosed and confirmed by the dealership, which identified the coolant control valve as the failed component. To my knowledge, GM has not yet inspected this specific failure. Prior to the loss of power, the truck displayed a “Reduced Engine Power” warning message and the check engine light on the dashboard. These warnings appeared at the time of the failure. Importantly, GM has already acknowledged this issue by issuing Special Coverage N252508341 for 2021 and 2022 GMC Sierra 1500 trucks with the same LM2 engine and the same coolant control valve part numbers. However, the 2020 models (like mine) were excluded from that program despite using the identical part and engine configuration.

--Radio power button inoperative --Radio channel change buttons, to left of steering wheel inoperative (everyday) --Radio volume inoperative -just stops working (sometimes) --Radio “HOME” button, left of radio power button inoperative --Driver door mirror wobbles when above 50 MPH (very distracting when driving) --Driver door hard to close and out of alignment --Dealership is selling the vehicles KNOWING some of the issues are present, but not advising the buyer. My safety is/was at risk due to having to move my hands off the steering wheel to touch the radio display to make any changes while driving. A certified GM service dept confirmed all my issues and could not repair. They quoted a PIT 6408. However, this particular PIT does not address my issues/concerns.

My 2018 GMC Yukon blew an engine with only 81,000 miles. Had four shops including (2 GM dealerships) look at the vehicle, pictures, and findings and concluded the engine had blown. The vehicle had began running very rough while driving down the road at 45mph. The CEL showed a misfire in cylinder one. The spark plug was pulled and soaked in oil. A borescope was put down the hole and found oil pooled on top of the piston. The engine has blow by the piston rings and the cylinder wall was scorn. Four shops. Four results. New engine needed. A quick google search of the engine (L83) showed multiple open class action lawsuits for this exact situation. The cause of the problem is the active fuel management system that GM created. When I contacted GM for assistance at the recommendation of the dealerships (which they have seen an increase in these engine blowing with low miles) I was informed by GM/GMC that they would look into it and could not guarantee assistance. Fast forward a couple of days I was contacted and made perfectly aware that I was 991 days outside and 21,000 miles out of warranty but they would offer “assistance” in the amount of 10% of the total cost. Four shops, four quotes for an engine replacement ranging from $14,750-$17,000 and GM was only offering $1,475-$1,700. Absolutely terrible. With multiple open class action lawsuits, stop sales, and well documented issues. I expressed disappointment and requested assistance to prevent having to seek litigation. I was told “if that’s what you want to do, you will need to talk to our legal department” and told there’s nothing they can do. Will not buy nor recommend anyone buy a GM product. They don’t respect or care for their customers.

Received message "Steering assist is reduced. Drive with care". This is related to a faulty thermostat and temperature sensor.