2023 GMC Yukon Powertrain & Transmission Problems

The 6.2L motor in my GMC Yukon failed due to the camshaft and stalled me in an intersection on a highway. Had to shut the lanes down to get towed. Lost all power and couldn’t do anything but sit in the road. Just did a PICO test and it “passed” but failed 3k miles after the recall was done.

I just survived a terrifying incident that proves the current GM 6.2L (L87) engine "recall fix" is a dangerous myth. Living with the "Ticking Time Bomb" I bought my 2023 GMC Yukon AT4 brand new, but for the last two years, I haven't truly "owned" it—it has owned me. Every long-distance trip with my family was filled with anxiety. I constantly worried that I’d be the next one stranded on the side of the road while my neighbors' and friends' 6.2L engines were seizing all around me. I traveled with fear that I’d be coming home in a rental car. The False Security of the Recall When the recall finally arrived, I thought the nightmare was over. On Sept 15, 2025, my dealer in Newburgh, NY, inspected the truck at 48,000 miles. They told me my engine "passed," switched the oil to 0W-40, and issued me a 150,000-mile extended warranty. I realized then what I know for sure now: 0W-40 oil is a band-aid, not a cure. GM used thicker oil to "cushion" a physical manufacturing defect in the crankshaft and bearings just to avoid the multi-billion dollar cost of engine replacements. They traded my family’s safety for their bottom line. The Catastrophic Failure Last Friday, March 13, 2026, the "fix" failed. I was traveling 70 mph uphill on I-84 with my **newborn baby** and two other kids in the back. Without warning, the engine seized solid. I lost all propulsion in heavy traffic and had to fight to get my children to the shoulder. We sat in the freezing cold for over an hour while traffic flew by us. An extended warranty is worthless when your engine dies in a high-speed traffic lane with an infant in the car.

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.

On 3/3/2026 during the night-time hours, I was traveling on the freeway in my 2023 GMC Yukon at over 65 MPH when I received a notice from the instrument cluster stating that the battery was low and oil pressure was low. Before I could pull over to a safe location, the Yukon turned off while in motion. My wife and two children were in the vehicle. The Yukon stalled in the number one lane of the off-ramp. I had to remove my children and wife from the vehicle while in the roadway on busy throughfares and in darkness. I attempted to jumpstart the Yukon, but efforts were unsuccessful. The Yukon was towed to the dealership where I purchased it purchased from. The Yukon was returned to my custody on 3/10/2026 stating it was an issue with the battery. While driving the Yukon home it began to bog down and stalled out in-front of my residence as it was being driven by my wife. After arriving home (night-time), I went to check the Yukon, and it started with no issues. I drove the Yukon to see if the errors would occur again. While driving the Yukon on the freeway, the Yukon RMPs indicated close to redline and I received a notification from the instrument cluster stating to turn the vehicle off (traveling at about 70-75 MPH). Once again, I was unable to pull off to a safe location before the Yukon turned off on its own while still in motion; I attempted to jumpstart the Yukon but attempts were unsuccessful. The Yukon was towed again to dealership. On 3/11/2026 I was advised that the engine had seized and on 3/13/2026 I was advised by GMC the engine needed to be replaced (this was covered under powertrain warranty). The approximate milage of the vehicle is at about 42,200.

Vehicle developed hesitation. Message: "Reduced Acceleration Drive with Caution" Check Engine light comes on, fortunately near home. Scanner showed "PO 0747 Transmission Valve #1 stuck open." Research shows this is a common problem and a safety issue and can leave driver stranded or worse. Had vehicle "serviced" at selling dealer, but they did not touch the transmission. Said they drove it around the block and it was fine. Image attached. I was then told that parts are not available and GM will not authorize swapping out the valve body. Forums posts show a lot of dissatisfaction with GM over this issue.

the Engine started running rough and the engine light came on. The dealer told my wife to drive there in limp mode (~15 miles), she did so on back roads. The diagnostics said that cylinder 7 was not firing and teh fuel injector control circuit was bad. they had to replace the Engine Control Unit.

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

The vehicle drove fine had no warning/ check engine lights. My girlfriend came up to a busy intersection and when she proceeded to cross the intersection the vehicles motor locked up stopping the vehicle in the middle of the intersection with traffic coming from both north and south direction. We had poor visibility due to blowing snow so she had to bail from the vehicle and stand on the side of the road so she would not be harmed if the vehicle was t boned. Vehicle stopped so hard and fast it threw her into the steering wheel. Was unable to get the vehicle restarted and could not get it to shift into neutral so vehicle blocked 1 lane of traffic completely and half of another lane until tow truck arrived to remove from road.

The contact owns a 2023 GMC Yukon. The contact stated that while driving 75 MPH and depressing the accelerator pedal, there was an abnormal clunking sound coming from the front of the vehicle; however, the contact was unsure if the failure was coming from the engine or transmission. The contact pulled over to the right side of the road, exited the vehicle, and inspected the vehicle, but found no failure. There was an unknown warning light illuminated. The contact stated that the failure had occurred on four occasions. An unknown dealer was contacted. The vehicle was taken to a dealer, where it was diagnosed, and determined that the valve body needed to be replaced. The valve body was replaced. The manufacturer was not notified of the failure. The approximate failure mileage was 33,395.

Vehicle was brought to dealership Fountain Buick GMC 8701 S Orange Blossom Trail, Orlando, FL 32809 (866) 465-4364 for recall on engine. Dealership told our company that they were unable to repair or diagnose the recall this month June 2025. Vehicle has had an intermittent check engine light from time to time. I was instructed that it was safe to still drive the vehicle.

My name is [XXX] , and I am writing to formally lodge a complaint regarding a serious safety defect in my 2023 GMC Yukon with a 3.0 Duramax diesel engine. The issue involves the transmission valve body, which has caused rear wheel lockup at highway speeds. I experienced this issue at 34,000 miles on my vehicle, and it has been in the shop for over 5 weeks with no estimated time on parts availability. Despite opening a case with GM support, as detailed in the attached email transcript, I have not received a resolution. GM has refused to replace the complete transmission on the vehicle and only offered to replace the valve body. This is unacceptable as the defective valve body has already caused damage to the transmission. I also opened a BBB Auto Line case, which was closed immediately after I denied the offer from the GM support representative. This raises concerns about a potential conflict of interest, as the BBB Auto Line seemed aware of my interactions with GM support. I am seeking a complete transmission replacement with a valve body upgrade kit from NextGen transmission, which I believe would resolve the issue. However, GM has not accepted this offer. I request that the NHTSA investigate this matter promptly to ensure the safety of my vehicle and others that may be affected by this defect. If this issue is not resolved, I will have no choice but to pursue legal action. Thank you for your prompt attention to this matter. Sincerely, [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On April 30, 2025, my 2023 GMC Yukon with 68,000 miles on it (8,000 miles outside of the warranty and that I had purchased on 4/27/2024) randomly downshifted as I was turning into a parking lot and gave me a computer notification stating "Service transmission now, unable to shift soon." I immediately put my car in park and called OnStar for her to read me the computer code. She said it came up with two codes so we brought it to Wyatt Johnson GMC in Clarksville Tennessee. They plugged in their computer reader and that's when the service provider informed me that my car was un-drivable because it was unsafe. We left it there for them to do a diagnostic test on it to see exactly what is wrong with it. A few days later they contacted us and informed us that it was a malfunction in the transmission valve body. The dealership informed us that it would cost $2754.25 to fix but the issue is the part is on back order and they don't know when it will be available. We have been in contact with the dealership and with General Motors customer service almost weekly trying to find out, when the part will be available and where I am on "the list" and no one has an answer. With the personal research that I have done, I have seen that people have been waiting for over a year. I also know that there are current class-action lawsuits for GM's Yukons for years a little older than mine and currently multiple complaints for the newer Yukons for the same transmission valve body issues. The dealership does not give out loaners anymore after Covid. I have asked, general motors. Customer service has informed me that it's up to the dealership if they will give me one General Motors said they would look into a possible reimbursement program if I have to purchase a rental, but they will only cover a car that cost $44 a day and that is not including taxes and extra fees, but I can't afford to rent anything and I'm missing work.

The contact owns a 2023 GMC Yukon. The contact stated that the vehicle failed to reverse as needed. The contact stated that the transmission was stuck in neutral. The contact stated that while driving 35 MPH, the transmission was slipping. There were no warning lights illuminated. The vehicle was towed to the local dealer, where it was diagnosed and determined that the valve body needed to be replaced. The dealer informed the contact that parts were on backorder. The vehicle was not repaired. The manufacturer was contacted, and a claim was filed. The failure mileage was approximately 72,000.

Vehicle has 32,000 miles and the valve body has gone out and now parts for possibly months. My vehicle has been in the shop over these first 2 years over 2 months. Now this issue with the valve body it has been in over two weeks and they claim it will be months before they can get parts. This issue puts the vehicle in limp mode and most likely is damaging the clutrch packs as they go out. People all over the forums are having issues with these 10 speed transmissions. Something needs to be done to help out those affected.

My engine failed while I was driving & I had no warning. It was very scary & dangerous. Luckily I was in an area where I could get off the road quickly. It started skipping then lost power. I basically coasted off the road & had to call for help. It was making a bad knocking noise. This happened 2 weeks ago on April 16. It has been sitting at Glynn Smith.GMC dealership since. I was told by the service manager that the engine failed & I will need a new engine. the engines are on back order now. I fear they will replace it with the same problem. I see the recall this week but will changing the oil viscosity really fix it?? Doubtful. Someone is going to get killed or hurt from this problem. I do not want the same issue to happen with a new engine.

While driving on the mass pike with my fiancé and 4 kids our motor suddenly died. We were using cruise control going 75mph and the vehicle shifted into neutral itself and the car died. I managed to make it to a break down lane and we had to sit there for 2.5 hours before a tow showed up to help. The dealership said the motor seized and we were under the 60K for warranty and it was covered. They got us a rental the next day and then on the 3rd day they called and said it was lack of oil changes that caused it and they asked if i had records of service history. We bought the vehicle used and only had the vehicle long enough to perform 1 oil change. We did our oil change on time and I'm trying to locate service records from the dealership we bought it from. However there were no signs of dark and contaminated oil when i did the oil change at my shop and also no sounds or warnings coming from the vehicle prior to the motor seizing up. I think they are trying to get out of paying for the motor when its clearly a known problem with these 6.2l engines.

Looks like this is a ongoing issue with my vehicles engine. The truck has 40k miles on it and the entire engine blew.

On March 28, my 2023 Yukon Denali stalled on a 4 lane road forcing me to make an emergency stop on the side of the road in a right hand turn lane. The vehicle required towing to a local GMC dealership. They could not restart the vehicle and upon evaluation found metal shavings in the oil. They have recommended an engine replacement. There was no warning, it just stalled and would not restart. My Yukon remains at the dealership and we are still waiting for an engine.

The engine lost power then suddenly stopped running while driving on an interstate.

The contact owns a 2023 GMC Yukon. The contact stated that while driving 70 MPH, the vehicle independently shifted into neutral and stalled in the middle of the highway. An unknown message was displayed. In addition, after restarting the vehicle, the accelerator pedal was depressed but the vehicle failed to accelerate as intended. The contact stated that the transmission then shifted into neutral(N) independently after driving for several miles. The contact stated that the vehicle would not crank and was towed to a local dealer. The contact stated that the vehicle failed to shift into neutral and was towed while in park(P). The vehicle was diagnosed and determined that the engine needed to be replaced. The vehicle was not repaired and remained at the local dealer for further investigation. The contact related the failure to GM investigation: PE25001. The manufacturer was made aware of the failure. The failure mileage was approximately 20,549.