2021 GMC Yukon XL transmission problems

Filed Sep 30, 2026 · Transmission · IN

Rear wheel lock up for a slight second and then down shifted and revved way up to high RPM then went into reduced power. then slowed down and had to drive about 15 miles an hour. to shop mechanic.

Filed Sep 22, 2026 · Transmission · MO

While driving the vehicle on a roadtrip in Missouri, the engine lost power and had a flashing check engine light. Upon diagnosis by three different technicians, the 6.2L Engine needs replaced after only 123000 miles. The lifters and camshaft have failed. This is a known safety issue and numerous recalls have been implemented, but my high end Denali is mysteriously absent from the recall. This is unsafe and unsatisfactory.

Filed Sep 1, 2026 · Engine, Transmission · IL

Vehicle is equipped with the 6.2L L87 V8 engine. Prior to receiving the dealer service for Recall 25V‑274, the vehicle experienced a distinct highway vibration, powertrain shudder, and fluctuating/jumping RPMs on the highway. The dealer subsequently performed the recall remedy by updating the vehicle to the thicker 0W-40 oil specification. However, the underlying transmission torque converter had already suffered catastrophic failure due to the powertrain stress/shudder and required a complete transmission replacement at 84,000 miles. I am reporting this because the initial 6.2L engine defect and subsequent recall remedy overlap heavily with severe powertrain and torque converter failures at low mileage

Filed Aug 24, 2026 · Transmission · TX

2022 GMC Yukon XL suffered catastrophic transmission failure at approximately 87,000 miles. An ASE-certified transmission repair facility determined that the torque converter failed, resulting in transmission damage requiring over $7,000 in repairs. GM declined any assistance solely because the repair was performed by an independent ASE-certified facility. I am concerned that a major transmission component failure at this mileage may represent a broader defect, particularly given transmission-related service bulletins and the federal safety agency Recall 26V085 affecting certain 2022 Yukon XL vehicles.

Filed Aug 21, 2026 · Electrical, Engine · IL

Driving on busy road when heard a squealing from the engine bay of the vehicle. Moments later the vehicle lost power. It was a very dangerous situation traveling approximately 45mph on a multi-lane road in urban St. Louis Missouri. There was not a check engine light prior. The vehicle had a recall performed per GMC instructions prior (this amounted to a different viscosity oil....). The breakdown stranded my family and I while on vacation in another city. The vehicle was towed to a local GMC dealership and was diagnosed as a seized engine related to the recall. The engine is scheduled to be replaced as no cost through GMC's extended service. They have not provided coverage for the towing, for the multiple ride shares needed to get around on vacation, for the rental car needed to get home, or a rental car to help us with day-to-day life during the estimated 6-8 weeks we will be waiting. My family was at risk, other motorists on the parkway were at risk. It was pure luck and quick thinking that saved injury or loss of life. It is completely unbelievable GMC is letting these vehicles be on the road for peoples safety and for the money people pay as a consumer.

Filed Jul 3, 2026 · Engine, Transmission · SC

My family and were traveling to visit family, and the transmission stalled on me on the interstate. I almost had a horrible accident with my kids in the vehicle. The vehicle is in the shop currently and dx with transmission issues. GMC needs to recall and or fix the transmissions in all of their vehicle.

Filed Jul 1, 2026 · Engine, Transmission · KS

Issue Description: The vehicle experienced a failure of the Dynamic Fuel Management (DFM) system, resulting in a collapsed lifter. This caused a cylinder misfire and a sudden loss of engine power while driving at highway speeds. Safety Concern: While traveling at highway speeds, the sudden misfire and loss of power created a dangerous condition. The vehicle could not maintain speed or accelerate properly with surrounding traffic, significantly increasing the risk of a collision. Failure Details: The issue was diagnosed as a collapsed lifter related to the DFM system. This caused persistent misfiring, rough engine operation, and severe drivability issues. Repair Outcome: Due to the extent of internal engine damage caused by the lifter failure, the vehicle required complete engine replacement.

Filed Jun 6, 2026 · Engine, Seat belts · OR

While I was driving home from the grocery store with my 4 kids our 2021 GMC Yukon XL (5.3L V8 engine), the vehicle suffered a sudden, catastrophic mechanical engine failure without warning. The engine began violently shaking, lost major propulsion, and dropped into a severe misfire state when we were coming down the highway. This created an immediate safety hazard on the road, as I suddenly lost the ability to safely accelerate or maintain highway speeds while hauling my children.A certified technician diagnosed the issue as a complete failure of the active fuel management hydraulic valve lifters and bent pushrods, a known manufacturing defect explicitly documented in GM Technical Service Bulletin PIP5776F. The internal failure required a total engine teardown and valvetrain replacement, costing over $10,000 out of pocket.General Motors has failed to issue a safety recall for this specific 5.3L valvetrain defect, despite it causing unexpected engine stalls, severe power loss, and immediate traffic hazards for drivers. This defective component poses an ongoing safety risk to families and should be upgraded to a mandatory safety recall. I am afraid to drive it every time I get on the highway in fear it could shut down again.

Filed May 11, 2026 · Engine, Fuel system · IA

The vehicle drove normally earlier in the day with no major drivability concerns. Later, reverse gear suddenly stopped functioning and the engine would rev abnormally without the vehicle moving properly while in reverse. Shortly afterward, while driving, the vehicle displayed the warning message “Reduce Acceleration – Drive with Care” and began losing acceleration and propulsion. The vehicle would not accelerate normally and later could not exceed approximately 20-35 MPH. The condition created a significant safety concern due to sudden loss of acceleration and propulsion while operating in traffic. The engine RPM would increase abnormally while the vehicle failed to respond properly in drive and reverse. An independent mechanic inspected the transmission and found diagnostic trouble codes P0747, P0776, and P0700 related to transmission pressure control and valve body operation. Inspection also revealed significant metal contamination, sludge, and clutch material inside the transmission pan and filter. Reverse and 2nd gear were determined to be failed/burnt internally. The vehicle was later transported to an authorized GMC dealer for inspection. Dealer confirmed reverse gear would not engage even after adding transmission fluid. Vehicle is currently available for inspection.

Filed Apr 16, 2026 · Engine, Fuel system · GA

The vehicle experienced a major engine failure involving the 6.2L engine. The failure appeared sudden and premature and is not consistent with normal wear and tear for a vehicle of this type. Prior to the failure, there were intermittent performance concerns and warning indicators suggesting potential engine or drivetrain issues. The vehicle had previously undergone repair related to similar concerns, indicating a possible recurring problem. The failure created a potential safety risk due to the possibility of loss of power while driving, which could increase the risk of an accident, especially at highway speeds or in traffic. The issue has been confirmed by a service provider, and the vehicle requires significant repair. General Motors has been notified but has declined repair assistance, classifying the issue as wear and tear. While no active recall is currently associated with this specific vehicle, similar vehicles with the same engine platform have documented issues, raising concerns about reliability and safety. The failed components are available for inspection upon request.