GMC Complaints

The contact owns a 2023 GMC Sierra 2500. The contact stated that his son informed him that there was a puddle of water in the rear seat. The vehicle was taken to the dealer, where it was diagnosed that the upper track for the rear sliding window was fractured on both sides, causing water to leak inside the vehicle. The dealer determined that the rear window needed to be replaced; however, the part was on backorder. The vehicle was not repaired. The manufacturer was notified of the failure and case was filed. The failure mileage was approximately 21,000.

When you go to park the car and put it in park the car says shift to park with it already being in park. It is concerning that the vehicle is not recognizing it being in park

I was driving on the interstate when my vehicle’s display indicated that I needed to press start and that is when I noticed the engine was not running. I had to quickly pull over moving three car lanes all while coasting and I came to a stop. I tried multiple times to restart but the engine would not restart. I still had electrical power and turned on my hazard lights and called for a tow truck.

While driving down the interstate the vehicle lost power without warning and gave a command to "press start to resume" tried to do that but nothing happened. Eventually we were able to get over to the shoulder of the interstate which was super busy in Atlanta. Once we stopped, we shut off the vehicle and it started back up, and we proceeded to get back on the interstate, when the same thing happened. We stopped again, waiting a few minutes and were able to get back on the interstate and complete out trip without any issues. 3 days later while driving on the interstate again, the vehicle had a weird winding noise coming from it. Once I was able to get off the instate the engine was knocking very loudly and had no power. Got the vehicle to our home and had it towed to the dealership the next day. Dealership gave the diagnoses that a new engine, radiator and engine coolant lines needed to be replaced. The vehicle had 2,248 miles on it and was purchase 2.5 weeks prior. No eta on when we will have a new engine and our vehicle back.

The contact owns a 2018 GMC Yukon XL. The contact stated while driving at an undisclosed speed, the vehicle stalled with no warning light illuminated. The vehicle was able to restart. The vehicle was taken to an independent mechanic where it was diagnosed with engine failure and the contact was informed that the engine needed to be replaced. The vehicle was not repaired. The vehicle was towed to the dealer where the same diagnostic result was provided to the contact. The contact was informed that the engine needed to be replaced. The vehicle was repaired; however, the failure recurred. The manufacturer was not made aware of the failure. The approximate failure mileage was 70,000.

The contact owns a 2022 GMC Sierra 1500. The contact stated that while company driver was driving the vehicle at an undisclosed speed, the driver noticed an abnormal knocking sound coming from the engine. The driver turned the vehicle off. The vehicle was restarted; however, the failure reoccurred. The vehicle was taken to the dealer where it was diagnosed with a lower engine knock. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact was informed that the parts to repair the vehicle were on backorder. The contact stated the vehicle had been at the dealer since February 25, 2025, awaiting the repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 64,000.

While driving under normal conditions the panoramic sunroof shattered. This is a serious safety issue and obviously a problem with the manufacturing of the tempered glass

Driving on the highway, moving to pass another vehicle, engine shut off forcing me to coast to the shoulder. No warnings and didn't notice loss of power until I saw that the vehicle had been shifted into neutral. Had 2 kids in the truck and could not get GMC service department on the phone, had to walk up an onramp in order to get my kids home with me in an Uber. This is a 2024 6.2L GMC with only 13,000 miles. Service department took over a week to check initial issues, said it was a fuse block which they replaced. Did not resolve the issue, then it was the starter, which did not resolve the issue, after 2 weeks they told me the engine was locked up due to internal failure and it will be several months before the truck is operable. GM has stated they the issue needs to occur 4 times before a buyback would be considered.

According to dealership Front and Back Suspension - SHOCK &/OR Struts - According to all complaints online it could be the Magnetic Ride Control- Car is a danger!!!!!! This car bounces all over the place - rides rough and bumpy!!! This should not be happening at 84K miles!

The 6.2 engine started ticking now. It needs to be rebuilt. It's ridiculous. We service it every 3000 miles. Our 2017 Sierra had a valve stick that ruined the cam. It has the same 6.2 engine with only 78,000 miles on it.