2023 GMC Yukon

GM has failed to resolve repeated issues on my vehicle (VIN: [XXX] ). I was never notified of any official buyback denial. GM Customer Assistance continues to avoid clarifying the status and refuses to provide documentation of the denial. This creates an unresolved safety and reliability concern. I need an investigation into the consistent mechanical defects paired with GM’s refusal to properly process my claim. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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.

The contact owns a 2023 GMC Yukon. The contact stated that while driving 40 MPH, the vehicle unintendedly decelerated and failed to exceed 10 MPH. The message "Reduced Acceleration" was displayed. The vehicle was driven to the residence. The vehicle was then towed to the dealer, where it was diagnosed that an unknown transmission part needed to be replaced; however, the part was on backorder. Additionally, the contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling), which the contact related to the failure; however, the part to do the recall repair was not yet available. The dealer was contacted. The vehicle was not repaired and remained at the dealer for 11 months. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure, but no assistance was provided. The failure mileage was approximately 37,000. VIN tool confirms parts not available.

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.

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)

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.

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.

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.