2023 GMC Yukon

The check-engine light first appeared at approximately 42,000 miles. I dropped the vehicle off at the dealership on August 22 and picked it up on September 1. Within TWO MILES of leaving the dealership, the check-engine light came right back on. The dealership initially diagnosed the problem as a lifter and wiring-harness failure. They later determined that the #7 oil-lifter solenoid had an internal short, and the wiring harness was replaced because of damage related to that short. What I still don’t have is an answer to the most important question: What actually caused the failure? Based on everything I’ve read about the problems surrounding GM’s 6.2L engines, I’m concerned this is only the beginning. These are extremely expensive vehicles—with monthly payments that can rival a mortgage—and owners shouldn’t have to wonder whether the engine is going to become an ongoing problem at 42,000 miles. Extending the warranty is helpful, but it doesn’t address the underlying issue or restore confidence in the vehicle. If these 6.2L engines have a known systemic defect, GM should be required to provide a permanent solution—whether that means replacing the affected engines or offering owners a fair buyback. Consumers paid a premium price. They should be able to expect a premium vehicle that is dependable.

My vehicle was with ANCIRA GMC Boerne for approximately three weeks where they replaced the transmission control system/module, the centralized OnStar module, and diagnosed both rear screens for replacement. Approximately one month after getting it back, at only 49,800 miles, I experienced a complete loss of propulsion. The vehicle shut down while I was driving. Given the recent transmission repair and the fact that this failure occurred while the vehicle was in motion, I no longer have confidence in the safety or reliability of this vehicle. I have young children riding in this vehicle daily and I’m not comfortable accepting another repair and simply being told it’s safe to drive.

My 2023 GMC Yukon AT4 with the 6.2L V8 has experienced multiple serious engine-related failures. The original engine previously was making a whining / knocking noise, then seized and required complete engine replacement under a GM recall/campaign involving 6.2L engine failures. The replacement engine later developed a lifter/valvetrain failure and required lifter replacement. The vehicle is now again exhibiting a pronounced rhythmic mechanical knocking/tapping noise, primarily during cold starts after sitting for an extended period. The noise occurs on most cold starts and has been documented in multiple videos. The vehicle is currently at a GMC dealership for inspection. I provided the dealer with several videos clearly demonstrating the noise. The dealer has stated that it has not yet been able to reproduce the condition and is attempting additional cold-start testing. The exact cause is currently UNKNOWN. No consistent warning lights or dashboard messages have appeared with the current knocking condition. My concern is that this vehicle has already experienced a catastrophic engine seizure, followed by internal valvetrain/lifter failure in the replacement engine, and is now again exhibiting abnormal mechanical engine noise. I am concerned this may indicate another developing internal engine failure that could potentially result in engine seizure or sudden loss of power while driving, including at highway speeds or in traffic. The vehicle and engine remain available for inspection, and multiple video recordings of the recurring cold-start knocking are available.

On August 22, 2026, I was driving my 2023 GMC Yukon Denali with the 6.2L V8 at highway speed when the vehicle began struggling to maintain power while climbing a hill. The engine then developed a noticeable knocking sound. Shortly afterward, the engine shut off completely while the vehicle was moving, causing a sudden loss of propulsion. I was able to bring the vehicle to a stop, but the engine would not restart. The electronic transmission also would not shift into Neutral and displayed a message indicating that the conditions required to shift were not met. Because the vehicle could not be shifted out of Park, the towing company had difficulty loading and unloading the vehicle. The failure occurred during normal highway driving and created a significant safety concern because the engine shut down without warning while the vehicle was in motion. I am aware of NHTSA Recall 25V-274 / GM Recall N252494000 involving certain GM vehicles equipped with the 6.2L L87 engine, as well as NHTSA Engineering Analysis EA25-007 concerning engine failures and loss of propulsion. At the time of this complaint, the dealership has not yet confirmed the specific mechanical cause of my vehicle’s failure. The vehicle is being taken to an authorized GMC dealership for diagnosis. I am submitting this complaint because of the sudden engine failure and loss of propulsion while traveling on a highway.

Vehicle had previously undergone the GM 6.2L engine recall inspection on October 17, 2025, and was determined to have passed. On June 13, 2026, at approximately 80,390 miles, the vehicle suddenly lost propulsion while being driven with five children in the vehicle. The vehicle became inoperable and required towing. Dealer subsequently diagnosed engine failure and has ordered a replacement engine. This failure happened with out warning.

I was traveling with my family on the Ohio Turnpike. We were traveling west in our 2023 GMC Yukon Denali when we lost all propulsion and the engine seized. There was no warning lights or other symptoms prior to this incident on May 3, 2026. In fact, I had the vehicle in for the prescribed recall to test the engine for the known defect earlier in 2026. The vehicle passed that test and was given the upgraded oil change to presumably prevent the engine failure in the future. It did not work. Our safety and others on the turnpike were at risk while we were traveling at highway rates of speed with sudden loss of all propulsion. The vehicle was towed that evening to local GM dealer - Yark Chevy in [XXX] . Upon inspection on May 5, 2026, the dealership informed me the engine had seized and would be replaced by GM. They were unable to provide a timeline for this repair. I have the tow expense of $260.70 and now the uncertainty of when I might have a vehicle back. The safety of my family and all others traveling the Ohio Turnpike that date were at significant risk. The vehicle remains at Yark Chevy in Perrysburg, Ohio available for inspection upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My 2023 GMC Yukon Denali with the 6.2L V8 suffered a sudden loss of propulsion while traveling at approximately 70–75 mph on the highway with my wife and young daughter in the vehicle. The engine RPM dropped immediately to zero and the vehicle displayed a message instructing me to press start. I do not recall any meaningful prior warning lamps or symptoms before the failure. I did not hear a loud bang or other dramatic engine noise; the vehicle simply lost power and would not continue driving under engine power. I had to coast across lanes/shoulder to a stop, which created a serious safety risk to my family and other drivers because the vehicle lost propulsion at freeway speed without warning. After stopping, the vehicle would not restart. Pressing the start button produced only a click from under the hood and the engine would not crank. The vehicle was towed to a GMC dealership in Victorville, California. The dealer has since confirmed that the engine requires full replacement. The failure has therefore been confirmed by an authorized GMC dealer and the vehicle should be available for inspection through that dealership/manufacturer if requested. This is especially concerning because this vehicle was already part of the known GM 6.2L recall population and had supposedly passed the recall inspection/remedy before I purchased it. Despite that, the engine still failed catastrophically only about 1,355 miles into my ownership. Purchase mileage was approximately 26,343 and failure occurred at approximately 27,698 miles. Based on what the dealer told me, the failed component/system is the engine assembly.

2023 Yukon Denali has now broken down twice, leaving myself and my family (husband and children). This last time was on Friday 1/16/26 while we were out of town, the car began malfunction and then we had complete engine failure while drive 70mph down the highway, again, leaving my family stranded on the side of the road, on a busy highway, in an unsafe environment in the winter.

Engine Failed 1400 miles from home on 6.2L Engine - Days after getting L87 Engine Loss of Propulsion Recall Service. Recall Service Completed on 12/1/2025 - Cap and Oil Change done - Full Engine Failure on 12/22/2025. 12/1/2025 - L87 Engine Recall Service Done at GMC Dealership - Quincy IL 12/16/2025- Check Engine Light came on - went to same Dealership - Cleared it told me I was fine to drive across country 12/22/2025 - Full Engine Failure on GMC Yukon Denali