NHTSA Complaint #11708039 — 2021 GMC YUKON XL

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.