GMC Complaints

While driving approximately 63 mph on a busy roadway, my 2023 GMC Yukon experienced a sudden failure of the brake system, including loss of normal braking capability along with failures of the Electronic Stability Control (ESC) and ABS systems. The vehicle displayed warning messages stating “Brake System Failure” and “Service ESC” and entered a reduced-speed mode. Prior to this incident, there were no warning lights, messages, or symptoms indicating a problem. During the failure, the brakes became largely unresponsive, placing me, my two minor children who were passengers in the vehicle, and surrounding motorists at serious risk of a high-speed collision. After extended deceleration, a minimal amount of braking power partially returned, allowing the vehicle to eventually come to a stop. The vehicle has not yet been inspected by a dealer, manufacturer, police, or insurance representatives, and the issue has not yet been reproduced or confirmed by a service center. The vehicle remains available for inspection upon request and has not been repaired. This incident occurred without prior warning and involved a sudden and dangerous loss of braking capability at highway speed.

Back window leaks down onto electrical compents and causes mold behind rear seat, plus staining mold on headliner

I heard a loud metallic knock that was not consistent with normal engine noise. I noticed the oil pressure was on the lower end of the scale but not abnormal based on how it is displayed. I decided to take the vehicle to the dealer ASAP for an oil change (that was coming due) and discuss with them. I drove roughly 20 miles from start of noise until delivery at the dealer. The truck gave me a "Reduced Acceleration, drive with caution" message 10 miles prior to the dealership but no associated lights, engine codes, check engine light or associated alerts on the myGMC app. Dealership found oil pressure ranging between 4-8 psi, and a failed oil pressure control solenoid, heavy metal debris in the oil pan including parts of the thrust bearing and oil squirter. Entire engine and turbo replacement was required. Truck had 143 hours on the engine and 6,300 miles. It was produced in August of 2025 with a purchase date of 17 October 2025. Produced: 8/25 Purchased: 10/17/25 Failed: 12/30/2025 Returned with new Engine: 1/23/26

suddenly went into limp mode on the highway, engine had to be replaced due to bearing failure sending metal through the engine

i was driving down the road the front piece of the grill flew off the truck and hit my windshield, then flew into oncoming traffic.

GMC SUPER CRUISE MALFUNCTION NO WARNING BEFORE SUPERCRUISE SHUTS OFF PASSING A CAR ON FOUR LANE HIGHWAY (SUPER CRUISE ENABLED) SUPER CRUISE SHUT OFF AND TRUCK CONTINUED HEADING FOR THE CENTER GAURD RAIL.(I CAUGHT IT BEFORE IT BECAME AN INCIDENT). SUPER CRUISE ABRUPTLY SHUTS OFF (NO WARNING) AND WITHIN A COUPLE THOUSAND FEET IT TURNS ON. MY FIRST TIME USING SUPERCRUISE AZ HIGHWAY 87 N BOUND JUST BEFORE RYE AND AZ HIGHWAY 260 BETWEEN PAYSON AND CHRISTOPHER CREEK I CALLED MY DEALERSHIP BUT IT WAS LIKE UH HUH OK I'LL LET GM KNOW.- NO SUPPORT! THE ONLY INDICATOR IS ON THE STEERING WHEEL A RED,GREEN OR YELLOW LIGHT.RED IS OFF-GREEN IS ACTIVE, AND YELLOW LIGHT NO SERVICE. RED LIGHT COMES ON AND SEAT VIBRATES SUPERCRUISE DROPS OUT.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving at various speeds, the braking system had erroneously activated, causing the vehicle to abruptly stop in the middle of the road. The vehicle was towed to the local dealer, who diagnosed that the failure was caused by an engine malfunction of the number six cylinder. The vehicle was repaired. No further information was available. After retrieving the vehicle, the contact was driving approximately 10 MPH when the failure reoccurred and the braking system erroneously activated, causing the vehicle to abruptly stop. During the incident, the driver's head slammed into the steering wheel, causing a head laceration. No medical treatment was required. The vehicle was towed back to the dealer. The cause of the failure was not yet determined. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 120,000.

My vehicle recently experienced a sudden flashing check engine light, severe misfiring, and rough engine operation, creating an unsafe driving condition. An inspection by an authorized GMC dealership, Serra Buick GMC Champaign, confirmed a failed deactivating valve lifter on Cylinder 5, documenting that the lifter ceased movement after a single engine rotation. The dealership advised that the failure necessitates replacement of all lifters and extensive internal engine components, at an estimated cost of $5,650.75. This defect is not isolated, unforeseeable, or the result of consumer misuse. It is directly associated with General Motors’ Active Fuel Management (AFM) system, which has been widely reported to cause: •Premature lifter collapse •Camshaft damage •Severe engine misfires •Loss of power while driving •Catastrophic engine failure

My truck is affected by GM’s engine block-heater safety recall (NHTSA 21V-496 / GM N212329840) addressing a risk of short circuit and potential engine-compartment fire at the heater cord/terminal connection. GM’s interim action has been to remove/disable the block-heater cord, which my dealer did, and then marked the recall “completed.” As a result, the NHTSA VIN tool shows 0 unrepaired recalls, even though no actual repair/restored functionality exists and GM continues to advise owners not to use the block heater until parts are available. Safety concern / impact: I live in a cold-weather area and purchased this diesel expecting a functioning block heater for reliable cold starts. Disabling the heater has removed an intended cold-weather safety/starting aid for multiple winters without a final fix. GM’s bulletin explicitly allowed dealers to disable the cord to close the recall, rather than provide a repair, leaving owners without the feature indefinitely. Suspiciously, I have also had to replace glow plugs on this truck sooner than traditional wear / failure rates would demand - including one glow plug that has been replaced twice in short span of time (should have lasted years). I continue to monitor GM’s recall portal; still no parts/remedy schedule. Please review whether GM’s chosen remedy—disabling a safety-related feature and closing the recall—is adequate and within a reasonable time under the Safety Act. If not, I request NHTSA open a Recall Query into remedy adequacy and timeliness so owners receive a real repair (replacement heater/cord/connector) or appropriate alternative remedies.

I was driving on the interstate when the hood deflector blew off suddenly and unexpectedly damaging my hood and hitting the windshield. This vehicle was recalled for this part defect last year and the fix was applied by the dealer. It appears that some sort of adhesive was applied to the retainers but they still ultimately failed. This was a very dangerous situation that could have ultimately caused an accident. I am reporting this so that the approved repair can be reviewed. This part should have been replaced, not simply placing adhesive on the defective part. The past safety recall # was N242490120.