GMC Complaints

The Car has over the last few years not turn off due to shift to park. This is concerning, due to we cannot turn the car off unless we strike the shifter few times assuming this is the remedy. It doesn't look like there is any type of recall but there should be.

Sudden engine issue. Knocking, power loss, brake and steering warnings. Severely damaged engine. Mechanic says 2 cylinders are irreparably damaged and entire engine must be replaced

Cruise control activates at speeds below 2 mph which frequently happens while turning or parking. The cruise control activates by a toggle on the left spoke of the steering wheel which can be easily bumped while doing low speed maneuvers like parking. When bumping the toggle the cruise indicator shows a set speed of 15mph and the vehicle surges forward trying to attain that speed. Since this occurs while maneuvering to park, it creates a dangerous situation if anyone is nearby and you are unable to react in time. This is an ongoing problem that can be duplicated at will.

I bought the vehicle in November of 2025. No warning lights or problems running. Check the engine oil upon purchase and have the dealership sticker showing oil change was recently done and oil showed that it was full. Approximately 3 weeks after purchasing, the car starting idling rough and stalled a few times during my commute to work. The check engine light came on and it showed that the vvt was a possible solution for the code P0014 this was on December 12th 2025. I replaced the suspected part with no change in vehicle condition. I checked the oil and found that it was empty/no oil on dipstick. I had to add 5 quarts of oil and then it showed it was in the safe zone on the dip stick. Today (January 15th 2026) I checked the oil again and it showed no oil on the dipstick. I had to add 2 quarts for it to be at the bottom of the safe zone on the dipstick.

26’ GMC Sierra 1500 AT4 3.0l Duramax experiencing Harsh shifting occurring sporadically while accelerating and deceleration. More frequent and severe during quick deceleration. Severe clunking/rear wheel lock up while reversing. Very repeatable. Truck was a dealer demo and had 2400 miles on it when I bought it last week. Took it in to the dealer today and they said I need a complete new transmission.

Truck went in service 9/17/2025 because the wheels locked up while driving. Transmission was replaced. Picked up truck and 2 hours later the truck shut off while driving and was started back up and was limp mode. Was told wire chaffing and they taped and rerouted wires. Picked truck back up and next day it did the same thing. Took back to the dealer and they said wires again. They taped wires back up and we picked up the truck. We had it 7 days and while driving down the expressway the whole truck shut off and would not start up again. Clearly that is a safety issue. After sitting on the side of the expressway for 10 minutes it started up again and was in limp mode and taken to the dealer again. I don’t know what has been done to it yet as they are not great at communication but they have had our truck for 4 months minus the 7 days we had it before it had to go back to the dealer.

[XXX], our 2017 Terrain Denali displayed code: “Low Oil/Shut Engine Off” so had it towed to Laura Buick/GMC Colllinsville, IL. Laura confirmed the issue was blown rear seal due to design of intake cover and PCV. They checked with aftermarket warranty for VIN [XXX] , warranty contract number [XXX] who said it was not a covered issue. We called Warranty folks also and were told it was an “external issue” and not covered. Appealed to GM Customer Service who said VIN was not covered. The vehicle has approximately 83,000 miles and we referenced PIP5093B and Special Coverage Program number SB-10057977, and Special Coverage Adjustment 16118 Excessive Engine Oil Consumption. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle was shaking abnormally. No warning light was illuminated. The vehicle was taken to the dealer to be diagnosed, and it was determined that the engine needed to be replaced. The vehicle was then taken to an independent mechanic, who determined that the torque converter had failed. The torque converter was replaced, but the failure persisted. The vehicle was taken back to the independent mechanic, who replaced the torque converter a second time. The manufacturer was not made aware of the failure. The failure mileage was approximately 140,000.

The contact owns a 2012 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission unexpectedly downshifted, especially between second and third gears. The check engine warning light was intermittently illuminated. In addition, the contact stated that the engine felt as though the engine mounts were inoperable. The contact pulled over to the side of the road and turned off the vehicle. The vehicle was restarted, and the vehicle resumed normal driving. The vehicle was taken to the dealer; however, no cause for the failure was found. The vehicle was not repaired. The contact stated that the failure persisted. The manufacturer was made aware of the failure, but no assistance was offered. The failure mileage was approximately 20,000.

We are located in Henderson, NV and we were driving on the freeway in a construction zone with no emergency lanes when the vehicle lost all power to the engine going the speed limit. The engine had seized up which is a known problem with the 6.2L GMC motors. We have done all the recalls recommended by the manufacturer. The engine seizing, locking up , put our family in danger . We were luckily enough to be close to an offramp where people in other vehicles barley let us over so we can pull off the road or we would of been stuck in the middle of the highway with cars flying by us with little kids in the car. This is unacceptable and as much as this happening and GMC not fixing the issues, people are going to get hurt or killed. IT IS A HUGE SAFETY CONCERN! . ThIS is a known issue with these motors and problems and GMC is putting bandaids on the situations when lives are in danger. Our truck is a 2023 GMC Yukon Denali with only 53k miles on it