GMC Complaints

Vehicle purchased 8/31/2025 October 20, 2025 "reduced acceleration" alert while driving on why up a significant grade with no way to pull off to the side of the road. Speed limitied to 35mph. Stopped by dealership pulled PO6DD code. Appointment made for November 12th. November 12, 2025 routine oil change and service noted "unable to duplicate concern on vehicly, currently no P06DD is present only DTC that was found in history was U1643 Lost communications with transmission control module can bus 2. cleared DTCs and test drove vehicle and is operating normal no issues. unable to duplicate." December 4th, 2025 driving on interstate and "reduced acceleration" alert...pulled into nearest dealer and code "P06DD" pulled. December 5th, 2025 returned to home dealership "Found Code P06DD. As per TSB#25-NA-307, checked the crankshaft end play, found the crankshaft has excessive end play. This is an indication of a worn thrust bearing. As per TSB engine Replacement is required." Vehicle currently has 6,800 miles.

I started to notice changes in performance around 75k miles. Seemed like performance was subpar compared to what was the norm. Seemed to lose some power. Minimal at first, more so just recently around 90k. Oil consumption was starting to accelerate at each oil change at 75k, 80k, 85k, 90k. To the point around 85k and 90k that I would not go over even 1 mile from the 5k threshold without changing the oil. Around 90k I could tell it was not getting any better, deficiencies were accelerating it seemed. At 91k miles I started to hear clicking noises and loss of power, starts were getting rough, bouncing at idle. I stopped driving it, only driving it to the dealership where I brought for a look at it. Will be driving it again for them to do a deeper diagnostic. Many misfires at cylinder 5. PO305 the issue. Showed up around 91k miles on 12/17/25 Now investigation into my model. I see online.

I own a 2025 GMC Sierra 1500. The rearview camera is inoperable at night (image is too dark). Brought vehicle into to purchasing dealer with complaint. After service, I was told that there was nothing they could do to correct the issue. I then contacted GMC customer service. They advised to bring the vehicle to a different dealer and upon completion to contact customer service again. I did as advised and took the vehicle to a second dealership with the same result. As you are aware, this is a violation of federal law and a serious safety issue for small children, pets or any object behind the vehicle in the dark. Based on what I have been able to discover there are many people with this same complaint. GM is not addressing this issue and is as unwilling to assist others as they have been to assist me.

Vehicle has 56000 miles currently and at 47000 transmission had to be replaced due to defective valve body. At 56000 miles, motor was replaced due to broken lifter. The vehicle currently will not start.

On December 1, 2025 at around 5pm CST, my 2021 GMC Yukon XL started making a squeeling noise then stopped while driving down the road. It left me stranded in the middle of the road. A P0016 CODE was produced and the engine light came on. I had the vehicle towed the next day to Stew Hanses GMC in Clive, Iowa. The engine was torn down for inspection and was told the rod bearing went bad and it had low oil even though I was within the window since the last oil change and having documented all necessary required maintenance. I was told the engine needs to be replaced and am in the process currently of Stew Hanson GMC replacing all necessary parts. I was told I do not have a recall on the vehicles vin number by GMC corporate and the GMC dealer. It is coming up on a month since the incident happened and vehicle towed to dealership. I do not have pictures from the dealer yet or final invoice as this is still in process. I wanted to document this somewhere.

traction control system ESC system Suddenly and without warning, multiple warning lights started flashing including check engine. The vehicle lost power and traction. There was a loud knocking and metallic whining sound. The vehicle began to vibrate and struggled to move forward and felt like the wheels were slipping. The loss of these functions was alarming because it was dark, we were in a construction zone, and my 15-year old daughter was driving having recently earned her driver's permit. The car following us almost rear ended us. It was such an abrupt engine failure it scared me and my daughter.

The lights on the dashboard is indicating that the hood is unlocked and the security system is being tampered with. Hood is closed and it disengage auto start and the alarm goes off every 10 minutes.

The windshield defroster and heater blower speed reduces and/or shuts off shortly after accelerating to highway range speeds. Blowing snow from Alaska roads will melt and refreeze on the windshield reducing visibility creating a safety hazard. The truck has not been successfully repaired after multiple and lengthy attempts. The heated steering wheel also malfunctions intermittently. The blower motor does seem to come back up to speed when vehicle speed is reduced to city speeds but is intermittent also.

I purchased my 2024 GMC Sierra 1500 on July 4, 2024. Shortly after purchase, the vehicle began experiencing recurring electrical and electronic malfunctions affecting multiple safety and driver-assistance systems. These issues include power mirrors not consistently folding when the vehicle is locked, the digital speed (MPH) intermittently not displaying on the dashboard, driver seat memory not always setting upon entry, and blind spot warning indicators activating while driving when no vehicles or objects are present. More critically, the rear parking assist sensors do not function consistently and often fail to alert before contact with an object. I have backed into objects on multiple occasions before the sensors activated or without any warning, creating a safety risk while reversing. I first brought the vehicle to the dealership on January 13, 2025 for these issues, but they were not resolved. I purchased two GMC-branded trailer cameras in December 2024 that are advertised as compatible with this vehicle. On September 1, 2025, I returned to the dealership when the “invisible trailer” feature became inoperable. The trailer camera system frequently shows a black screen, cuts out intermittently, or fails to display an image. I returned again on September 11, 2025 due to continued failure of the invisible trailer feature and rear parking assist. The dealership kept my vehicle until December 2, 2025 (approximately one month), but the issues remain unresolved. I am scheduled to return again in January. These failures reduce rear visibility and compromise multiple safety systems. Despite repeated dealership repair attempts and extended service time, the problems persist, suggesting a defect involving the vehicle’s electrical system, sensors, software, or camera modules. I have photo and video documentation of these failures.

I was driving up the road truck cranked up fine started a morning commute, on cruise control the truck instantly out of nowhere lost power completely with no signs of anything and engine won’t attempt to turn over now. I fear the worst has happened which would be catastrophic internal failure for to a faulty engine & its internals.