2025 GMC Sierra 1500 Other or unknown Problems

“Tailgate switch Tailgate opened on its own with trailer attached while driving damaging the top of my tailgate. No notification inside cab. No console / fob / tailgate buttons were pushed. Discovered tailgate was down after I arrived home and had done a wide u-turn in my back yard. So far dealership has done very little diagnostic wise. Two trips to dealership so far with little to no results. …”

“Safety Complaint – Delayed Acceleration from Automatic Engine Stop/Start I am reporting a safety concern regarding the automatic engine stop/start system in my GMC truck. During normal operation, the system shuts the engine off when the vehicle comes to a complete stop. When I release the brake and press the accelerator, there is a noticeable delay while the engine restarts before power is delivered to the wheels. This creates a hesitation between driver input and vehicle response. …”

“Upon purchase of my 2025 GMC Sierra, it did not come with a physical manual. I asked the dealer about this and they said they did away with them, only providing the digital version. I contacted GMC recently as I saw the a recall dor 2026 models with this exact issue, but they did not seem to care and it was for 2026 models only. I find this to be a loophole GMC is following, and would just like a manual so I can log maintenance like a normal person without a phone or sitting in my vehicle. Thank you”

“Either while stopping while driving or parking (forward or reverse) the engine RPMs go up thus wanting to move the vehicle in that direction causing the breaks needing to be applied harder. When you shift into neutral the RPMs go way up (3000). This has happened on this vehicle 3-4 times of which I have video of the latest occurrence. When put into R or D the RPMs are still over 1000. This also happened on the courtesy vehicle same make and model) I was given but on this one the RPMs went up to 5000 of which I also have a video. …”

“Driving down interstate highway and sunroof “exploded”. Raising glass sunroof up about 2” above the body. Vehicle had 387 miles on it. This occurred at about 6:55 am and outside temperature was about 74 degrees. The rupture was loud and very startling and I exited the interstate pulling over to see what occurred. There was no damage whatsoever to any other body component and no “flying” debris was observed at anytime that could have struck the vehicle. I requested GMC dealer to look at onboard cameras and save video but they seemed dismissive. …”