GMC Complaints

The OnStar System completely shut down. The module stopped working while driving and now there is no communication to the vehicle.

Pulling into a driveway and the truck made a loud clunk and the check engine light, traction control light, and a reduced engine power light came on and the truck came to an abrupt stop. When the gear shift was put into reverse or any forward gear the truck would rev up without touching the gas pedal. The left rear wheel locked up. After paying over $700 in tow bills to get the truck towed to our house and then to the dealer we were told that the transmission had a catastrophic internal failure. This truck only has 82,000 miles on it and is a 2021!

The contact owns a 2021 GMC Sierra 1500. The contact had received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The vehicle was taken to the dealer where an inspection was performed on the engine. The contact was informed that the vehicle had passed the inspection, and the mechanic added a higher viscosity oil, installed an oil fill cap, replaced the oil filter, and updated the Owner's Manual. The contact stated that the remedy failed to address or repair the possible defect with the engine. The contact stated that the remedy resulted in a higher cost for oil changes, and fuel economy had decreased from 21 miles per gallon to 18 miles per gallon. The manufacturer was made aware of the issue and the contact was provided a case number. The contact stated that the vehicle had not been repaired. The failure mileage was unknown.

We have experienced multiple recurring issues with our 2024 GMC Acadia that raise significant safety concerns and affect the vehicle’s reliability and overall operation. First, the brake system exhibits persistent squeaking, even at low speeds or light applications. The dealership has inspected the brakes but the noise continues, raising concerns about premature wear or improper brake function. More concerning is the behavior of the automatic braking system while reversing. The system has repeatedly activated the brakes without any obstacle, vehicle, or person behind us. These unexpected braking events have created both physical and psychological stress for occupants and pose a real risk of causing a rear-end collision from another driver who may not anticipate sudden braking. Due to this hazardous condition, we have been forced to deactivate the automatic braking feature entirely, defeating a critical safety system the vehicle is equipped with. Additionally, the engine frequently runs rough during cold start and the initial warm-up period for the first couple of minutes. This rough operation is inconsistent with expected behavior for a new vehicle and has not been fully resolved despite service visits. The TPMS sensors have also been problematic. Several sensors have already been replaced by the dealership, yet we continue to experience intermittent TPMS faults involving at least two wheels. This results in repeated warnings, loss of real-time tire data, and uncertainty about actual tire pressure conditions while driving. We also experience rattling noises from the interior trim near the door seals whenever there is a cross breeze or windy driving conditions. This appears to be a structural or insulation-related issue. We have others, but this space only allows for 2000 characters, and after writing this sentence, there are only 113 characters remaining.

In December of 2023 my 2020 GMC Sierra 1500 was driving down the freeway, experienced a jerking and low oil pressure. Pulled over and shut vehicle off and wouldn't turn back on, engine locked up. The vehicle received a brand new 6.2l replacement motor in April of 2024- $15k in parts and labor. This vehicle was not included in the recent recall, but obviously experienced a similar issue. This was at 75k miles. The car was owned by a different owner at the time of the engine failure. I bought the vehicle as a repo and proceeded to get the engine fixed on it.

The contact owns a 2017 GMC Yukon XL. The contact stated that the check engine warning light was illuminated. The contact stated that while idling, the vehicle started shuddering violently. The contact stated that while driving to the residence at an undisclosed speed, the vehicle stalled and failed to restart. The vehicle was pushed into a church parking lot. The contact's father used a scanner to scan the vehicle, and a DTC for engine misfire was retrieved. The contact's father replaced the spark plugs, but the failure persisted. The vehicle was towed to an independent mechanic, where it was diagnosed and determined that the engine was blown. The vehicle was then towed to another independent mechanic, where the engine was replaced. Additionally, the contact stated that upon depressing the brake pedal, the brake pedal was stiff and required to be pumped several times for the vehicle to respond as intended. The contact stated that the failure occurred while starting the vehicle and while driving at various speeds. There was no warning light illuminated. The contact stated that the brakes had been replaced annually, but the failure persisted. The contact stated that the brake pedal shuddered upon starting the vehicle. The contact received a notification for ABS from the OnStar Mobile App. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 148,246.

I was driving down the highway at 65-70mph and the top part of the grill flew off, causing scratches to the wind shield. There’s has been a recall on this for 2022 GMC 1500 Sierra’s but I am driving a 2024 and the issue is still the same.

The contact owns a 2018 GMC Terrain. The contact stated that while driving approximately 30 MPH, the brake pedal became extremely difficult to depress, with the message "Brake Assist" displayed. The vehicle was driven to the shoulder of the roadway and the parking brake was activated, and the vehicle was turned off. The contact stated that the transmission failed to shift into gear, and the vehicle was dragged onto a flatbed truck and towed to the residence. The cause of the failure was not yet determined. The local dealer and manufacturer were notified of the failure, but no assistance was offered. The failure mileage was 132,386.

Every winter when the temps dip into single digits something on the truck freezes and causes a major malfunction. This winter (2025) is the second time I’ve had a problem with the truck freezing up and leaving me in “limp mode”. Last year the same thing happened. The def sensors freeze up and the heater shorts out leaving me stranded in my $70,000 truck. I now have 34miles remaining until my truck is limited to 55mph. This is a serious problem.

The upper radiator hose on a significant number of these trucks is failing prematurely. In my case, the failure occurred at just over 35,000 miles. Numerous reports on owner forums (such as the Colorado Chevy / GMC Canyon forum), YouTube, and other platforms document the same issue, indicating this is not an isolated incident but a widespread defect. Because this hose is part of the cooling system, its failure can quickly lead to engine overheating and potentially catastrophic engine damage. The root cause appears to be an engineering flaw in the sealing method: GM uses a rubber seal instead of a durable, high-quality o-ring to connect the upper hose to the radiator. Despite the seriousness of this defect, my local GMC dealer informed me that—since it is not currently a recall item—they could only schedule service for the following week, requiring me to leave the truck with them for 7–10 days before repairs would be completed. This is unreasonable for consumers who rely on these vehicles daily. Given the safety implications and the potential for engine failure, this issue warrants immediate attention. It should be classified as a recall item. Thousands of examples are already documented online, and GM’s own repair data would likely reveal thousands more instances of this same failure.