2021 GMC YUKON Complaints

I live in Alaska. It was -13f. We were out and about and when I tried to leave and back up, the vehicle would not go into reverse. If it hadn’t been for a passing motorist my daughter and I would have been stuck there overnight, in negative temps. I was able to drive it home, in limp mode. Come to find out, it is the valve body on the transmission. That in cold temps the valve body can fail. After some research I found that it is a KNOWN issue with these vehicles and there has even been a “Urgent-Distribute Immediately” Service Update regarding the problem. Urging dealerships to review the VIN’s they have in their possession for the issue. I had the vehicle towed to a shop, where they confirmed the problem was the transmission valve body. They were unable to perform the work as it takes a qualified technician to replace. So it got towed to the closest GMC dealership. They have had it for two weeks now. They confirmed that it is a known issue and there have been no recalls. But they did tell me I was “in luck” because they stock that item so we won’t have to wait for a part. Not only is it going to cost me $3500 to replace something that is a know issue with this vehicle, but it could have ended in tragedy if no one would have come along when we were stranded. I urge you to make this a recall on these vehicles.

I was driving down the highway at normal speeds under normal conditions and the engine light came on and started flashing. By the time I could find a safe place to pull over I heard the engine knocking. Left my wife, two young kids and myself stuck in the middle of the road with traffic coming. Managed to get it out of the road before going to get my truck and trailer to tow it home. I assume this is due to the L87 recall but mine was built in 01/21 and the recall is said to cover 03/21 and up. We don’t really know what to do at this point being its my wife and kids only way to work and school.

The car suddenly experienced engine failure while driving at highway speed (about 70 mph). The check engine light, as well as several other warning lights (Traction control, electronic stability control, etc) came on immediately before a metal-on-metal clunking sound and then loss of power. I was able to pull the car over to the side of the highway, and because of the clunking sound, felt it was unsafe to drive further and had it towed to a local dealer. The car has about 42,000 miles on it, in perfectly maintained condition, with all services performed at the Dealer per the recommended schedule.

The contact owns a 2021 GMC Yukon XL. The contact stated that while driving at an undisclosed speed, the vehicle lost drive power with several unknown warning lights illuminated. The vehicle was towed to an independent mechanic, who determined that the engine had seized and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and advised the contact to report the failure to the NHTSA Hotline. The failure mileage was approximately 22,000.

On [XXX] driving to Denver the 52,000 mile yukon started making a clicking sound when accelerating on the interstate. Traction control light came on as well as the check engine light. Low power was noticed and we immediately pulled over as it sounded like it was going to blow up. Towed the vehicle 145 miles where we bought it and the shop confirmed the lifters and 5th cylinder are the issue and that the cams could be damaged. Recommend replacing each side. The car is basically new and under the 60K drive train warranty but about 100 days past the 5 year mark. Terrible timing. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I was driving and a message popped up "Service Traction Control", then another message popped up "Forward Collision System Unavailable". Then the car started making this knocking sound and every time I would try and accelerate there would be a loud sound and almost a pulling stopping it from picking up much speed. I took the car into the dealer/repair shop and they said it was an issue with the lifters that had to be replaced and potentially an issue with the cam. They said this repair would cost upwards of $6,000 and I have never had this issue with the car before. This came out of nowhere and the car had not been showing any signs of this occurring before. This is a 2021 GMC Yukon and I drive my Wife and three sons in that car daily.

On Christmas Day while driving on the highway, I noticed a ticking sound coming from the engine. Our 21 Yukon Denali just hit 85,000 miles. I first noticed the traction control light was became disabled and then the check engine light started flashing. The sound escalates when you step on the gas. It appears that the lifters and cams are damaged on the vehicle and had to be towed to a dealership were it currently waits to avoid further damage. I was advised by the dealership that this particular vehicle is not part of the engine, recall notice, but heard that they might be expanding vin numbers to the recall as more incidents occur. They did confirm that the lifters and Cam’s are the issue.The vehicle has had a great maintenance record and was just at the same dealership five weeks earlier for oil change.

12/16/25 (evening): Warnings began cycling across the screen: 1) Service ESC, 2) Vehicle Leveling for Stability, 3) Rear Axel System Off, 4) Engine symbol began flashing, and 5) Service Traction Control. I felt vibration/bouncing while driving as well. 12/17/25 9 AM: Took 2021 GMC Yukon Denali to GMC dealership. They ran a computer scan and reported a misfire, but nothing else appeared to be wrong. They told me that sometimes a low battery can cause the warning lights and messages to cycle. They recommended that I keep driving it and return if the warnings appeared again. 12/17/25 9:18 AM: I left the dealership. I drove 4.5 miles, and all the same warning lights came back on. When I pulled into a parking lot, it smelled like my engine was on fire, and dark smoke was coming from my rear exhaust pipe. I called a flatbed tow truck and had the car returned to the dealership. Mileage: 52,285 GMC 2021Yukon Denali XL 6.2L V8 engine Well-maintained with regular oil changes. The dealership told me there was a lifter failure and that the engine could be damaged and would need to be replaced if the cam, pushrods, etc., were damaged. They also told me I was out of warranty by less than 60 days. The dealership said my warranty expired in October 2025, even though my vehicle is a 2021 with only 52,285 miles. They just informed me that the left lifter was replaced at 6,000 miles and that they will replace the right lifter. I am concerned about further damage down the road, given the recalls on the GMC 6.2L engines.

Driving the vehicle on the highway when I started to hear a ticking sound from the engine. After a few minutes, the check engine light came on and started flashing, traction control shut off and some system related to the rear end shut off. After inspection, it appears to have dropped a lifter.

While driving on a two lane road, my vehicle put itself into Neutral without me doing anything and the engine stopped. All things powered down. The engine stopped. not propulsion, nothing. I tried to pull over to edge of road. Car would not start - no activity. The vehicle had to be towed to the dealership. My safety was put at risk by my car simply stopping while driving down the road. The dealership has confirmed the engine needs to be replaced. There was no warning of engine problems or ANY indicators.