GMC Complaints

2017 GMC Terrain motors consume oil at an excessive rate (1 quart per 1,000 miles). Getting an oil change every 5,000 miles, even consistently, puts the engine at risk for major internal failure and safety risks to the passengers. My engine in my 2017 GMC Terrain has a broken timing chain and internal damage due to the excessive oil consumption issue. The engine will have to be replaced. GM has known about this issue for years. GM is in several lawsuits for this issue, but GM has failed to recall the parts of the motor that are excessively consuming oil. They refuse to help cover repair costs even though the costs are due to their poorly designed motor.

The contact owns a 2019 GMC Yukon. The contact stated that the third-row seats electrically controlled failed to function as needed. The contact stated that that the seats failed to move forward or backwards. The contact had taken the vehicle to a local dealer, where it was diagnosed and determined that the third-row seat unit needed to be replaced. The vehicle had not been repaired. The manufacturer had not been informed of the failure. The contact researched online and related the failure TSB: PIT5550C (Left Side Third Row Seat will not Power Fold/Unfold Seats, Electrical System). The failure mileage was approximately 34,000.

Driving approximately 45mph while car in front is approximately 50 yards ahead driving at a matched speed as my vehicle and without any prior warning the forward collision alert activated flashing red light on windshield and automatically applying FULL braking until the truck came to a complete abrupt stop in the center lane of rush hour traffic causing other drivers behind to swerve narrowly avoiding serious accident. Had the cars been following closer or an 18 wheeler been behind me during this incident, the outcome could have been much worse. I Manually de-activated the automatic braking but kept forward alert on until the truck could be brought to the dealership for diagnosis. Forward alert went off erroneously multiple times the following days without any rhyme or reason. Not until the final day before the scheduled service appointment did the system de activate itself indicating an issue with the forward collision. Most issues occurred while it was either raining or damp outside. Dealer now has vehicle in their possession and confirmed a faulty component that is on backorder with no date. Truck has had multiple other electrical issues since purchase 3 months ago. ~200 miles dealer replaced faulty HVAC module. ~4500 miles Forward collision alert as described above. Since day one there have also been Issues with trailering harness intermittently not working causing trailer brakes to not function while towing. (Yet to be diagnosed by dealer) Lastly Left turn signal would stick causing turn signal to stay on until manual deactivation. Dealer confirmed faulty turn signal and is in the process of replacing while it is in for service.

When the car is put In park there is a message that appears on the display when pushing start/stop to turn the car off "shift to park". The car has already unlocked and it turns off and restarts but the message keeps popping up

Transmission Control Module I was at an intersection when the TCM malfunctioned halfway through and I lost all power to my motor. I was pulling a large trailer and cross traffic had to slam on brakes to keep from hitting me. My truck will not move faster that a few miles an hour now that it is in limp mode. I am a police officer and I had an onboard diagnostic tool that showed that there was no communication to the TCM. Stabilitrack warning lamp and check engine light are now on. It all happened at once no warning.

Over the last 3 years we have had ongoing issues with our truck going into limp mode. We have spent thousands of dollars at dealerships and mechanics trying to troubleshoot the issue. Several occasions while trying to merge onto the freeway the truck would slip into limp mode causing us to have other drivers slam on their breaks almost hitting us. We had 2 cars in January of 2023 veer off the side of the road. We pulled over and thankfully they missed hitting one another. We just couldn't speed up to get out of their way. We cant believe their hasnt been a safety recall on the TCM for these trucks. GMC started doing Service bulletins in 2013 about the TCM causing the limp mode issues. There are dedicated facebook groups with over a 1,000 followers who are experiencing the same issues with these TCM's. Someone is going to die if they havent already. Several collisions, involving the years affected, are being re-investigated to determine why the vehicle slowed abruptly causing a fatal accident. A class action lawsuit is gaining momentum because GM will not do anything about the TCM.

The contact owns a 2017 GMC Acadia. The contact received notification of NHTSA Campaign Number: 23V334000 (Air Bags) however, the part to do the recall repair was unavailable. The manufacturer was contacted and confirmed that the part was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The local dealer was not made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

The contact owns a 2019 GMC Acadia. The contact stated while driving 55 MPH, the electric power steering (EPS) warning light illuminated, displaying the message "Steering assist Might be Inoperable". The contact stated that following the message being displayed, the vehicle overheated. After restarting the vehicle, the vehicle returned to normal functionality, but the failure had since become a regular occurrence. The vehicle was taken to the dealer, who diagnosed a failure with the thermostat. The vehicle was repaired. The manufacturer was notified of the failure but referred the contact to the NHTSA Hotline for assistance. The failure mileage was 70,000

My 2012 GMC Acadia has had numerous issues that all lead to the fuel pump assembly. Three separate times, my cars ignition has just shut off while driving. When trying to accelerate from a stop, the car will struggle to move then jump forward nearly hitting the car infront of me. Stabilitrak warning comes on. Car randomly jerks while driving. Car will randomly not want to start but eventually does after multiple attempts.

this yukon is leaking water into the cabin and mold has developed. i do not know when this issue started but i noticed the mold under the passenger rubber mat on 8/26/23. i contacted the local dealer, koon's gmc and they told me that they would charge me to just look at the car even though it is under a bumper to bumper 3 year warranty. the dealer was unable to locate the source of the leak, so nothing was fixed. i have been in touch with a gmc representative and she hasn't any useful information. the development of mold in the car is hazardous to our family and this should be looked into by the government.