GMC Complaints

Subject: Complaint Regarding Recurring Engine Failure in 2021 GMC Sierra AT4 Dear National Highway Traffic Safety Administration, I am writing to formally express my concern regarding recurring engine failures in my 2021 GMC Sierra AT4 (6.2L engine). At 23,000 miles, the vehicle suffered a complete breakdown due to failure of cylinder #8, lifters, and push rods. General Motors covered the repairs at that time. However, at 97,000 miles, the exact same issue reoccurred, resulting in significant engine damage. The dealership diagnosed a misfire in cylinder #8, leading to the removal of the right cylinder head, where they found a bent push rod, spun lifter, damaged camshaft lobe, and lifter roller. The repair estimate totals $9,746, but GM has refused to cover the costs, despite us having an extended warranty purchased from the dealership. This recurring failure raises serious concerns about engine reliability and manufacturing defects in General Motors vehicles. I urge the NHTSA to investigate this issue, as multiple GMC and Chevrolet owners have reported similar problems with the 6.2L engine lifter and camshaft system. This is not just a costly repair but a potential safety hazard that GM has failed to properly address. Thank you for your attention to this matter. I appreciate any guidance or action the NHTSA can take to hold GM accountable and ensure consumer protection.

Hi, I was driving on [XXX] and my radio volume went to full volume 100% by itself. The radio would not shut off and none of the controls would work, everything froze. I kept turning the volume button down and the volume bar on the screen showed that it was trying to minimize, but it wouldn't stay. It kept going to full volume. Finally, after I kept pushing the off and mute buttons, the radio shut off and was unresponsive. When I reached my destination and shut the truck off and restarted it, the radio then worked as it normally should. This happened to me yesterday, and I'm still having trouble hearing and my ears hurt. I researched this online and found that there are many other people that had this same scenario with their sierra. I wanted to reach out and report this. Thank you [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

At 9,100 miles my 2023 pickup truck experienced engine failure. It was inspected by dealership in the town where truck was purchased and it is determined that it will need a new engine due to "bearing failure". This occurred 2/24/25. No indicators or warning messages appeared.

Transmission failure - needed to replace the transmission Experienced rough shifting, slipping, or hesitation and then transmission failed while driving almost causing a multicar accident. This is a widely known issue for my vehicle year. GMC would not assist with any coverage of the repairs. This issue needs to be a recall.

The contact owns a 2023 GMC Yukon. The contact stated that while driving 70 MPH, the vehicle independently shifted into neutral and stalled in the middle of the highway. An unknown message was displayed. In addition, after restarting the vehicle, the accelerator pedal was depressed but the vehicle failed to accelerate as intended. The contact stated that the transmission then shifted into neutral(N) independently after driving for several miles. The contact stated that the vehicle would not crank and was towed to a local dealer. The contact stated that the vehicle failed to shift into neutral and was towed while in park(P). The vehicle was diagnosed and determined that the engine needed to be replaced. The vehicle was not repaired and remained at the local dealer for further investigation. The contact related the failure to GM investigation: PE25001. The manufacturer was made aware of the failure. The failure mileage was approximately 20,549.

at 60860 my first engine went out General Motors offered no help i have extended warranty it took 3 months to get my Yukon back now 40000 later 2nd engine goes out cannot get a dealer to touch excuse after excuse tried to contact General Motors nobody will talk to me

The contact owns a 2022 GMC Yukon. The contact stated while driving at an undisclosed speed, the message "Completely Out of Oil" was displayed on the instrument panel. No warning lights were illuminated. The contact stated that there was an abnormal sound coming from the engine compartment. The vehicle was towed to a dealer where it was diagnosed and determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 32,000.

We purchased our 2021 GMC Yukon used from a dealership 1 year ago with zero issues. 3 days ago out of no where there is a very loud squeaking sound in the front under the hood. No engine or warning lights just the sound. We had a mechanic check it and a part inside the tansmission is broke. NOT fixable, MUST be replaced.......

There was a problem with the catalytic converter that I was not aware of when I purchased the vehicle. There were no issues with performance for a few days until the engine began misfiring on the interstate and it forced me to pull over during heavy traffic. This was all in a week and the dealer has refused to take any responsibility despite being a Chevy Certified Dealer. I am now getting the vehicle repaired by my local mechanic due to the need for this vehicle. I have made General Motors aware of the situation.

Our family of 6 were traveling home on the Freeway, from a family road trip going about 75 mph. The engine revved up and then the entire car all electronics went black. And then flashed back on. A warning told me to "Start Engine" I attempted to, and it would not turn over. I was able to get to the shoulder to get us out of the hi-speed traffic. I put our hazards on, and the "Start Engine" warning popped up again. I attempted to start the engine again and it wouldn't turn over. All the warnings started to flash things like "check transmission, check battery.." etc. We asked our kids to stay buckled, because of the hi-speed traffic, and that it was dark outside, and we were in more of rural area. We called the nearest tow company, and had to wait about 30-40 minutes for him to get to us. The tow truck operator was not able to get the car in neutral to be able to get the Yukon on to the tow truck, he eventually got it on. The next morning the Service Tech called and said the car was completely dead when he got to it. Then, he called me later in the day and said he was able to look at the vehicle and run diagnostics and said the engine had seized. My car is less than 4 years old and had 66k miles. I had it serviced right before our family road trip at 64k miles. We have been the only owners and have always serviced it through GMC Service Centers Only. *Note*We had complained multiple times of a squeaking/chirping noise coming from the engine. Since we first received it. The service center kept the vehicle a couple of times overnight to try and diagnose. We had to pay for a new belt replacement, and the squeaking/chirping noise was never resolved. We wonder if this was a preexisting issue.