GMC Complaints

Sunroof shattered driving on the interstate. Never saw a rock or anything. I think it shattered due to pressure and temperature changes.

Since we purchased our 2022 Acadia 6/24/2022 we have had the warning "Service Safety Restraint System" pop up randomly. We have mentioned it numerous times over the years when the vehicle has been in for routine service at our local dealership. They have never been able to determine the cause as no service code ever shows up for them. Today in addition to the warning the red air bag warning light also lit up briefly. The warning has popped up 2x in the last 2 weeks again with today being the only time we noticed the red light as well. We are now more concerned about the safety of our vehicle. (We will be on vacation now through 8/25 & would be available after that date for any contact)

Unknown Truck engine will cut off in the middle of high speed traffic. More than three times.

Our lifters in cylinder 3 were replaced after failing at 40,000 miles. The exact same lifters broke again at 77,000 miles.both events caused engine failure.

While traveling with my wife and two toddlers over the July 4th holiday weekend, the 12 volt battery on my 2025 GMC Hummer EV failed completely at approximately 7,500 miles and five months of ownership. The vehicle would not accept a jump start and was disabled where it sat, stranding my family. AAA installed a replacement 12 volt battery roadside at a cost of $600. Following the battery replacement, a Service High Voltage System warning appeared on the dash and remained on, and the air conditioning system stopped functioning entirely. This occurred in Southern California summer heat with two small children in the vehicle. The HVAC loss and the high voltage system warning persisted for weeks. I brought the vehicle to a GMC dealership on July 15, 2026, repair order 978148, reporting the high voltage warning, the inoperative AC, and the battery failure. The dealership held the vehicle 7 days and performed no diagnosis. On July 26 I performed a 12 volt battery disconnect and reset myself, after which the warning cleared and the AC returned. No root cause has ever been diagnosed. The condition may recur. I am filing this because a sudden 12 volt system failure on this platform disables the entire vehicle, including a no-jump condition, and in my case produced a high voltage system warning and total HVAC loss. A 12 volt failure that strands a vehicle in traffic or disables climate control in extreme heat with children aboard is a safety issue, and NHTSA's complaint database already contains other electrical system complaints on this model year. The root cause of my failure remains undiagnosed by GM or its dealer.

SUV shut down when I was driving with no warning. OBD reader Code P129F Fuel pump power control Module is bad GM has recall #N252516900 lists my year and make of my SUV but my VIN# is not included and GMC said that it will not covered because the vin is not on the list.

The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving 70 MPH and depressing the accelerator pedal, the vehicle started decelerating unintendedly. The message “Engine Power Reduced” was displayed. A dealer was contacted. The vehicle was taken to a dealer where it was diagnosed and determined that the engine needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure and opened a case. The approximate failure mileage was 6,028.

The timing chain snapped and caused the engine to seize on our 2016 GMC Terrain 2.4L SLC-1 SUV/Truck. Since this has occurred multiple times on the 2.4L engines in this model from 2012 - 2016, we believe that there should be a recall as this issue could cause a major accident if the timing chain snaps or breaks while traveling. It had 101000 miles on it when we bought it used from Klein Automotive, on April 12, 2024. We have only had it for 2 years and 4 months and kept it in good repair. We took it in for its oil change, brought it home, went to dinner 4 days after and the very next day it wouldn't start. We thought it was most likely the starter/solenoid, but the mechanic said those were both fine and that's when we got the bad news that the motor was shot because the timing chain broke which caused some engine rods to break. The GMC dealer, in Marinette, WI, we brought our used 2016 GMC Terrain to, told us that the timing chain stretched and broke the rods in the engine and therefore both the timing chain and engine need to be replaced. The check engine light was turning on all of the time, and we were told that it was because it needed the 88 fuels (medium grade). As long as we put in the 88, the light check engine light stayed off. We believe there should be a recall for the 2012 - 2016 GMC Terrain SLC-1 2.4L timing chain and engine. We also need assistance with the cost of the repairs because I'm on a limited income and cannot afford the $10,000 cost of getting this repaired, while I still owe $7800 on it.

The contact owns a 2022 GMC Sierra 3500. The contact stated that while driving 65 MPH and depressing the accelerator pedal, the vehicle hesitated before going into LIMP Mode. A dealer was contacted. No warning light was illuminated. The vehicle was towed to a dealer where it was diagnosed with transmission control valve failure. The vehicle was not repaired. The contact associated the failure with NHTSA Campaign Number: 24V797000 (POWER TRAIN); however, the VIN was not included in the recall. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The approximate failure mileage was 71,000.

The vehicle’s headlights are malfunctioning, creating a safety concern. The issue was reported to the dealership and GMC Customer Care, but it remains unresolved. The dealership offered repair assistance, but GMC Customer Care stated that no additional assistance is available.