GMC Complaints

While driving I received a "service brake assist system" alert and a check engine light. After this happened the brakes were extremely hard to press. I had to put my entire weight on the breaks to stop the car. The brake "assist" feature really is making the brakes functional. We were able to safely get to the side of the road. We found a vacuum pump failed and needed to be replaced. There was no sign that this was failing; it worked, then it didn't.

My gmc sierra Denali 2022 equipped with the 6.2 motor locked up while I was driving pulling me out of the road.

Engine coolant control valve failure. This is a widespread issue on 2020-2022 3.0L Diesel trucks and it hasn’t been addressed by GM, leaving owners to pay out of pocket for a faulty part.

Vehicle will not shift out of park, despite replacing the valve body, putting in a new battery, and transmission fluid. It has been this way since mid January. The codes don’t make sense and there is no current recall, nor have we had this vehicle for very long. It has 48,000 miles on it and is having this issue. Very disappointed.

Vehicle exhibited a sudden loss of power, dash screen stated a restart of the vehicle was needed. I was able to coast into a neighborhood upon attempting to restart the vehicle nothing would happen and it would not even attempt to turn over, proceeded to contact onstar for roadside assistance, vehicle taken to nearest GMC dealership where it was determined to have engine failure and a new engine under warranty will be installed.

The contact owns a 2025 GMC Sierra 1500. The contact stated that while stopped at a traffic light, the gear shifter was shifted to park(P) and the vehicle stalled. The message "START Engine" was displayed. The vehicle was restarted, and the Auto START/STOP feature was disabled by pressing the "A" inside an orange circle. The contact stated that on another occasion while reversing into the driveway, the vehicle stalled. The message "START Engine" was displayed on the screen. The dealer was contacted; however, the vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired and the failure persisted. The manufacturer was not notified of the failure. The failure mileage was approximately 16,000.

The oil is depleting every month from the vehicle. Every 2-3 weeks I have to put oil in the vehicle because the oil is being absorbed. Is there a recall on this problem.

While driving the vehicle I received dash warnings of temperature rise. Pulled over and saw a large coolant leak coming from right side of engine compartment. Towed to dealership. Dealership informed me that coolant hose coming from heater core was routed by the manufacturer so that it rubbed on the frame. Dealer indicated problem persists on all vehicles and no given, other than replacing the hose and not remedy the problem. New hose will be in contact with frame again, causing inevitable where and breakage. Dealer did not cover under warranty nor did they offer solution for repair other than replacing those hose.

The contact owns a 2017 GMC Canyon. The contact stated that while operating the vehicle, the ABS and traction control warning lights illuminated, and the message " Check Trailer Brakes” was displayed. While driving at an undisclosed speed, the braking system randomly activated, causing the vehicle to abruptly decelerate. On several occasions while depressing the brake pedal, the vehicle failed to immediately stop, causing the braking distance to be extended by approximately 8 feet. The vehicle was taken to the local dealer, who diagnosed the vehicle and determined that the ABS module was faulty and needed to be replaced. The vehicle was not yet repaired. The failure mileage was 85,000.

The upper radiator hose on some huge percentage of these trucks fail (mine has failed at just over 37K miles). You can check the Colorado Chevy and GMC Canyon forums, youtube, Facebook, etc., et al, and find plenty of instances where this has failed. As this is the cooling system, it can cause the engine to overheat and potentially ruin the engine. The flaw seems to be an engineering issue with the rubber seal they use (instead of a high quality o-ring) to seal the upper hose to the radiator. Additionally, since this can cause engine failure it should be addressed immediately. Instead, my local Chevy dealer, since its not a recall item, said they could schedule a time next week for me to LEAVE the truck and that I am responsible for the repair. This is extremely unfair to the consumer who depends on these vehicles. This should absolutely be a recall item. You can find 1000's of examples online and if you can pull GM repair data, I'm sure you'll find 1000's more.