2023 GMC SIERRA 1500 Complaints

The contact owns a 2023 GMC Sierra 1500. The contact stated that when the vehicle was started and shifted into drive(D), the accelerator pedal was depressed, and the vehicle responded slowly. While driving at an undisclosed speed, the vehicle decelerated and stopped unintendedly. The "Parking Brake” warning light illuminated. The contact stated that once the vehicle had warmed up, the unintended stopping ceased. The contact stated that the failure was intermittent at first but had become a recurring failure. The vehicle was taken to a local dealer where it was diagnosed and determined that the valve body needed to be replaced; however, the part to complete the repair was on a national back order. The vehicle was not repaired. The manufacturer was informed of the failure. The failure mileage was approximately 60,000.

The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving uphill, the vehicle unexpectedly lost motive power. There was no warning light illuminated. The vehicle failed to restart and was towed to the dealer, where it was diagnosed, and determined that the engine block had failed and needed to be replaced. The vehicle was repaired. The contact stated that later, while driving at an undisclosed speed, the vehicle failed to shift into gear properly and jerked abnormally. There was no warning light illuminated. The vehicle was returned to the dealer and was diagnosed with transmission failure, requiring the PCM/TCM to be reprogrammed. The vehicle was repaired. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated, and the vehicle was taken back to the dealer, where it was diagnosed and determined that the fuel injector and coolant pump had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure, and a case was opened. The approximate failure mileage was 57,000.

2023 GMC SIERRA DENALI ULTIMATE 1500 WITH 6.2 V8 AT HIGHWAY SPEEDS 65 MPH THE CAR LOST PROPULSION AND SAID IT WAS IN NEUTRAL. CAR WOULDN'T SHIFT BACK INTO DRIVE. BARELY MADE IT OFF THE HIGHWAY WITHOUT AN ACCIDENT. CAR WOULDN'T RESTART. CAR BROUGHT TO DEALERSHIP AND WAS TOLD IT NEEDS A NEW ENGINE AND I WOULD BE WITHOUT MY TRUCK FOR A MONTH. CAR CURRENTLY HAS 20,200 MILES ON IT. PLUS NO LOANER CAR. GMC HAS TERRIBLE CUSTOMER SERVICE AND SELLS A DANGEROUS PRODUCT

I was driving on the Oklahoma turnpike @ 75mph when the engine locked up in traffic. I coasted to the side of the road and called roadside assistance. The truck is currently at Vance GMC in Miami, OK getting the engine replaced.

I am writing to formally file a safety complaint regarding the ongoing recall of the GMC/Chevrolet 6.2-liter V8 engine and what I believe to be an inadequate and insufficient remedy being provided to vehicle owners. I purchased a brand-new 2023 GMC Sierra AT4 equipped with the 6.2-liter engine. I drive approximately 6,000 miles per year and maintain the vehicle carefully. After receiving the recall notice, I promptly took my truck to an authorized GMC dealership for inspection and repair. The only action taken was an oil change to a heavier-weight oil. I was told that everything was “fine” and that no further action was required. I find this remedy unacceptable given the severity and nature of the reported failures associated with this engine platform. Simply changing to a heavier oil does not address the underlying mechanical risks and does not provide owners with meaningful assurance that catastrophic engine failure will not occur without warning. This issue is particularly serious for me because I rely on my vehicle for my livelihood. I am an account sales executive and use this truck extensively for work travel and customer meetings. If my vehicle were to fail unexpectedly, it could cause me to miss critical business meetings, resulting in immediate financial loss and potentially long-term damage to customer relationships and sales performance. The current remedy provides no confidence that such a scenario will not occur. In addition, this recall has materially harmed the resale and trade-in value of my vehicle. Dealerships are now significantly lowballing trade-in offers because the 6.2-liter engine recall is widely known and prospective buyers are reluctant to purchase these vehicles. Buyers are also aware that any future owner will not receive the benefit of the original powertrain warranty coverage in the same way, further depressing resale value. As a result, I am effectively trapped in a nearly new vehicle that has become difficult to sell or trade due

Tailgate is randomly dropping while driving without any tailgate drop buttons being pushed. It’s is starting to occur more frequently.

This malfunction is ongoing and the dealership cannot fix the problem. The first time it happened in September 2025. I was driving down the road and the gauges started to go crazy. The screen on the dash said reduced acceleration. Then it said Service ESC. Then it said Service Traction Control. It would not let me go over 40 mph. I took it to the dealership and they told me I needed a valve body replacement. They installed the valve body and that did not fix the problem. It happened again and said reduced acceleration took over forcing me to pull over on the side of the road. The GMC dealership said to bring it in again but they could not reproduce the malfunction after driving for a week. It happens randomly. The third time this happened I was traveling up interstate 24 at about 70 mph. There were semi trucks around me when the malfunction happened and my acceleration and speed was reduced throwing the RPMs as high as they would go, and I was almost hit by a semi trying to move out of the way and onto the shoulder of the interstate I tried to accelerate to get out of the way of the semi truck but could not. I had to swerve over almost losing control of my truck. I informed the dealership that this had happened again and they asked me to bring it in. I did. They told me they were going to clean corrosion off of ground wires, and that should fix the problem. It did not. This keeps happening and I feel that the vehicle is not safe to drive. I do not know when it will happen again. I travel for a living and I feel the vehicle is unsafe to operate.

I have a 2013 GMC 1500 with the 6.2L Engine. There was a recall on my engine when I purchased it used with 21K on the odometer. I took it in for the 5K oil change at 26K miles and the "performed the recall oil change" replacing the oil with 0W40 oil saying this should "fix the recall". At 32K miles my engine blew up on Christmas Eve 12/24/2025 and left my son and I stranded on the side of the road. I had the truck towed to the GMC dealer and they are now in the process of replacing the entire engine. I have now been without my truck for over a month because several other owners with 6.2L engines are having the same issue.

i was driving down the road the front piece of the grill flew off the truck and hit my windshield, then flew into oncoming traffic.

I have a 2023 GMC Delnali 1500 and the engine blew up 1-14-26 after the local CMC dealer 2 months ago done a check up recall from GMC that said they would do a test on the engine and cahnge the oil with a heavier weight oil that would solve the problem. After the dealer done the test and changed the oil to a heavier weight I was told all was good. Well 2 months later the engine blew up while I was driving down the road at 50 miles and the truck lost all propulsion. I had the truck towed to my house because noone knew what was wrong with it. I called the local dealer the next day and I had the truck towed to them. They checked the engine and said it blew apart and that GMC will replace the engine and also install a new radiator when all the parts are available. The dealership Laura Buick GMC and employees has been fantastic and have supplied me with a vehicle to drive till the repair is finished.