GMC Complaints

The vehicle was part of the GM L87 engine recall. The vehicle was taken to the dealership in late 2025 for recall service. The dealership inspected the vehicle for vibration and determined that it required an oil change and updated service manual to require 0W-40 oil. On June 21, 2026 the vehicle experienced an engine failure.

Lifter locked up causing bent push rod. This situation caused truck to strand the driver without warning. Truck needed to be towed. This repair was performed by the dealership and is a known issue with 6.2 L engine.

I got a yukon at4 and I had to replace it for the one with this vin number [XXX], the first one had a problem with the engine and the offer me to change it for a new one and accept it but since then it has given me problems, at first it was a small pull that felt, then an engine problem, that they "fix" and i have to come back because the " pull " still existed, they fixed it, and after around 3 months after, I had a an engine light one , collision light on, and ESC light one, took it to the dealer and it was something related with the engine again. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission independently shifted to park or neutral. The contact stated that the failure had occurred while driving at slow speeds. The contact stated that during one failure, the brakes independently activated, and the vehicle shut off. The contact stated that while attempting to restart the vehicle, the vehicle started. The contact stated that the failure was persistent. The dealer was made aware of the failure by phone. The vehicle was taken to the dealer; however, the diagnostic result was not provided. The failure mileage was approximately 500.

My 2022 GMC Sierra 1500 was subject to GM safety recall N242490120 / NHTSA 25V060 for an upper grille deflector that could detach from the vehicle. The recall repair was completed by my GM dealership in June 2025. In late August 2026, while driving normally on the highway, the same upper grille deflector detached again in the exact manner described by the recall. There was no collision, impact, or other outside damage that caused the failure. I was able to retain the detached deflector due to my attentiveness however, it was close to detaching and either busting mine or someone else’s windshield. Upon inspection, the adhesive and retainers from the previous recall repair are still clearly visible, and the bonding appears to have separated. I have photographs documenting the failed attachment points and still possess the undamaged detached component for inspection. My GM dealership inspected the vehicle after this failure and determined that the front grille assembly should be replaced. However, because the recall is shown as previously completed, GM has stated that the recall cannot be reopened. GM Customer Assistance offered only $251 toward a $1,673.82 repair, leaving me responsible for $1,422.82 to correct the same safety defect that the recall was intended to remedy. I am filing this complaint because the recall remedy appears to have failed, allowing the recalled component to detach from the vehicle again. A grille component detaching at highway speed could strike another vehicle or create a roadway hazard. I am concerned that other vehicles repaired under this recall may experience the same post-recall failure. I request that NHTSA review the effectiveness and durability of the remedy used for recall N242490120 / 25V060.

Dropping my children off at school, 4 lights came on on the dash. Two messages came across my dash as well. Service esc service abs. EBCM master cylinder needed to be replaced at local GMC dealership.My brakes were failing…This is a known safety issue by GMC and there’s no recall!

While driving my truck on the highway at 65 mph the truck bucked hard and immediately downshifted into 2nd gear. This caused me to rapidly decelerate to approximately 40 mph, I am lucky there was not another vehicle behind me when this happened since rapid unexpected deceleration without brake lights is very dangerous. I had to drive the truck in limp mode at 45mph and approximately 4500 rpms to the nearest exit. This event illuminated the trucks check engine light and displayed a brief service 4WD message followed by a permanent reduced acceleration message on the dash.

My 2021 GMC Yukon began experiencing severe engine problems, including shaking/rough running, a noticeable ticking/knocking noise from the engine, and a flashing check-engine light. The vehicle also displayed Service ESC and traction control warnings and exhibited symptoms of an engine misfire. I took the vehicle to a dealership for evaluation. I was advised that the problem may involve failed lifters and that the vehicle could be out of service for several weeks for repairs. I was also advised that the repair could be very costly. At this time, I have not been given a final diagnosis, so the exact internal engine component responsible for the failure is UNKNOWN. I am concerned that the condition presents a safety risk because the engine is running extremely rough and the check-engine light is flashing. I am afraid the engine could lose power or fail while the vehicle is being driven, potentially putting me, my passengers, and other motorists at risk. I have also become aware of NHTSA's investigation involving failures of the 6.2-liter L87 V8 engine in GM vehicles, including the GMC Yukon, as well as reports of engine failures occurring after certain repairs or recall remedies. This has increased my concern about whether repairing or replacing individual engine components will permanently resolve the problem. I am submitting this complaint so that my vehicle's symptoms, dealer evaluation, and potential engine failure are documented. The vehicle and affected components are available for inspection upon request. The dealership has evaluated the vehicle, but a final determination of the exact cause has not yet been provided.

Lifters failed under 80k miles. Had lifters replaced with gm parts and engine is continuing to eat up oil and lifters are failing again in less than 3 months after the repair. Vehicle was out of warranty and all costs were out of pocket including a rental for over a month bc parts were on backorder

I am reporting a serious safety concern involving a 2023 GMC Sierra 1500 Denali, 6.2L L87 V8, VIN [XXX]. This vehicle has now experienced two catastrophic powertrain failures at very low mileage. The first catastrophic engine failure occurred at approximately 23,696 miles. The vehicle was taken to a GMC dealer, where the repair documentation states that the engine had suffered significant internal damage, including damage to the #3 connecting rod, a missing connecting-rod bearing, bearing material throughout the engine, and a scored crankshaft. The dealer determined that the engine was seized and required replacement. GM replaced the engine under warranty with GM engine assembly part number 12740076. The vehicle has now experienced a second catastrophic failure. On [XXX], while traveling approximately 40 mph, experienced grinding, lurching, and knocking, followed by a complete loss of propulsion. The truck would no longer move and had to be towed to a GMC dealer. At the time of the incident, no warning lights or warning messages were observed. The transmission is also suspected to have failed, although the exact cause and extent of the transmission failure have not yet been determined by the dealer. I understand that NHTSA is currently investigating failures involving GM 6.2L L87 engines, including failures occurring after previous recall remedies and engine replacements. I am therefore requesting that this incident be included in NHTSA’s investigation and considered when evaluating the effectiveness of the existing recall remedy and the safety of replacement L87 engines. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)