2021 GMC Yukon Xl Problems

Engine coolant control valve has failed three times. This last time so severely the car forced me to come to a complete stop in the middle of a busy street. Dangerous to drive while severe reduced acceleration is all that’s available during the episodes.

Vehicle has been consuming engine oil at a rate of approximately 1 quart per 500 miles. On XXX, owner added 1 quart of oil in [XXX], then drove a round trip to [XXX] and back (approx. 860 miles). On XXX at 55,329 miles — only 9 days and roughly 860 miles after that quart was added — an oil change was performed at an independent shop; the technician noted no oil was present on the dipstick prior to service. On XXX at 55,829 miles — exactly 500 miles later — the vehicle was taken to an authorized GMC dealership, and the dipstick again showed no oil prior to service. The dealer began the manufacturer's oil consumption test protocol, performing an oil and filter change and other maintenance. Within approximately 74 miles of this service (current mileage 55,903), the engine began making an audible knocking noise. Oil level was checked and confirmed full/normal, ruling out low oil as the cause. The knock has been intermittent — not present at cold idle start, but returning during driving conditions, raising concern about potential engine failure or loss of power while driving. They can not get it back in till XXX. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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.

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

part number 13554821 fuel pump control module has failed 2 times. April 2023 on Interstate 95 near Savannah GA in very busy traffic. Vehicle buckled and seized, just barely made it to the shoulder of the road. Same part failed again 9/18/26 while turning onto Sunrise Hwy in NY another very dangerous situation as we were stranded in the middle of a very busy intersection

6.2L engine has the oil change update, and engine failed recently. took vehicle for repair to Golling GMC dealer. waiting on feedback.

Was driving the vehicle at 70 mph on the highway without any issues for several hours and suddenly the vehicle lost power and had no propulsion. It went into neutral automatically and the engine shut off while driving. Thankfully I was on a downward slope and could steer the vehicle off the very busy highway. Once safe, I tried to restart the car but the engine would not start or turn over. Roadside assistance came to help as well as a flatbed tow truck. It was taken to a nearby GMC dealer but it remains completely dead despite the battery being fully charged and all of the electronics working. No known error codes are showing up. It’s an L87 engine and was part of the GM recall. The recall work was completed in Nov 2025.

Check engine light comes on and an alert says "acceleration reduced" dealer says the coolant control valve is bad but the engine never overheats but the fans are running max speed 100% of the time.

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.

The vehicle has experienced recurring suspension, drivability, and pulling issues associated with the 4-corner air ride leveling suspension system since early ownership. The first major incident occurred at approximately 4,600 miles when the vehicle displayed suspension warnings and would not accelerate properly past highway speeds. Since that time, the vehicle has repeatedly experienced pulling during acceleration, unstable ride behavior, suspension/leveling concerns, alignment-related issues, and drivability instability. The problem has been reproduced multiple times and documented through approximately 16 repair visits and roughly 74 cumulative days out of service. Dealership service records include repeated suspension inspections, drivability evaluations, wheel alignments, and related repair attempts. The issue remains unresolved and the vehicle is currently back in service again for the same concern. The recurring pulling and instability create safety concerns because the vehicle does not consistently track properly during acceleration and normal driving conditions. Suspension warning messages and drivability symptoms first appeared early in ownership while the vehicle was still under factory warranty. I have also found many similar owner complaints online involving the same suspension system in comparable GM full-size SUV models.

I am the owner of a 2021 GMC Yukon Denali with the 6.2L V8 engine (VIN: [XXX] ). This vehicle has exhibited multiple serious issues affecting safety, drivability, and reliability. 1. Engine Noise & Oil Consumption: Since purchase, the vehicle has had a persistent loud knocking/tapping sound, especially under acceleration. The engine also consumes an excessive amount of oil between scheduled oil changes, with no visible leaks. I reported this to the dealership multiple times, but since there is no active recall or TSB, they refused to diagnose or repair the issue under warranty. I have since learned that many other 2021 Yukon Denali owners with the same 6.2L engine are experiencing similar issues and some have had repairs or engine replacements covered by GM. I have received no such support. 2. Braking Problems: The vehicle has ongoing brake performance issues. Despite replacing the brake components multiple times, the brakes feel inconsistent and unsafe, especially during highway driving or sudden stops. There is vibration and uneven response, and the braking system does not inspire confidence. These problems have persisted despite attempts to correct them. 3. Suspension/Handling Concerns: The suspension feels unstable and loose, especially at highway speeds or when turning. The ride quality is poor, and there is noticeable sway and body roll, which creates discomfort and concern for vehicle control. 4. Fuel/Propulsion System: The engine does not always respond smoothly to throttle input. I’ve noticed occasional hesitation or surging, which may be related to the previously mentioned oil consumption or fuel delivery. Again, the dealership has been unable or unwilling to resolve these issues without charging diagnostic fees. I’ve reported these issues to my local GMC dealer on multiple occasions, but no lasting solution has been provided, and I have not been able to afford expensive diagnostic costs out of pocket—especially for a vehicle of this price INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATIO

Car shakes in drive, car shakes when accelerating, transmission issues, rear differential had to be replaced.

The contact owns a 2021 GMC Yukon XL. The contact stated while operating the vehicle on a cold day, the windshield wiper fluid failed to spray from the windshield wiper nozzle and the windshield and window could not be cleaned while driving. The contact stated that the failure was present with the front windshield and rear glass and had created a visibility hazard for the driver. The cause of the failure was not yet determined, and the vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was offered. The local dealer was not contacted. The failure mileage was 48,000.

The wiper system turns off randomly when it’s raining…. It’s been taken in to the dealer multiple times but no changes made. Doesn’t matter if auto sensing is on or off.

The vehicle has experienced recurring suspension, drivability, and pulling issues associated with the 4-corner air ride leveling suspension system since early ownership. The first major incident occurred at approximately 4,600 miles when the vehicle displayed suspension warnings and would not accelerate properly past highway speeds. Since that time, the vehicle has repeatedly experienced pulling during acceleration, unstable ride behavior, suspension/leveling concerns, alignment-related issues, and drivability instability. The problem has been reproduced multiple times and documented through approximately 16 repair visits and roughly 74 cumulative days out of service. Dealership service records include repeated suspension inspections, drivability evaluations, wheel alignments, and related repair attempts. The issue remains unresolved and the vehicle is currently back in service again for the same concern. The recurring pulling and instability create safety concerns because the vehicle does not consistently track properly during acceleration and normal driving conditions. Suspension warning messages and drivability symptoms first appeared early in ownership while the vehicle was still under factory warranty. I have also found many similar owner complaints online involving the same suspension system in comparable GM full-size SUV models.

When driving at slow speed and wheels turning right or left you can hear a humming coming from the suspension. Unable to identify the issue. When wheels get straight the humming goes away

The contact owned a 2021 GMC Yukon XL. The contact stated that while driving 70 MPH, the “Service Safety Restraint Device” warning light illuminated. A dealer was contacted. The vehicle was taken to a dealer, and the contact was informed that the air bag was not repaired correctly because there was electrical tape and packing foam inside the air bag housing. The air bag was replaced and the front driver seat belt was replaced, and the vehicle was repaired. The manufacturer was notified of the failure and opened a case. The approximate failure mileage was 117,000.

The suv shown safety message, it was diagnosed with airbag not deployed. This is very important specially for the rear backseat. GMC doesn’t want to be responsible and makes customer pay.

When driving at slow speed and wheels turning right or left you can hear a humming coming from the suspension. Unable to identify the issue. When wheels get straight the humming goes away

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.

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.

When turning on the car, a message pops up on the dash and will not go away. Dashboard says “ service safety restraint system”

When driving at slow speed and wheels turning right or left you can hear a humming coming from the suspension. Unable to identify the issue. When wheels get straight the humming goes away

The chest clip button is not difficult to open. The chest clip is a button on this carseat instead of a buckle. My child, who will be 2 years old this month, has been able to unbuckle the chest clip for months now. I am concerned if an accident occurs and the chest clip is unbuckled, he will get seriously injured.

The contact owns a 2021 GMC Yukon Denali XL. The contact stated that during rainy weather, rainwater leaked into the vehicle through the drainage hose, causing an electrical short. The vehicle was taken to a dealer where it was confirmed that the drainage hose and wiring needed to be replaced. The vehicle was repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 55,000.

front grill is the Vader chrome and it is peeling off, GM told me there is nothing that can be done and this is a well know issue and is all over the forms. This is due to poor manufacturing quality. A car this expensive should not be having these issues

2021 GMC Yukon Headlight condensation with no accidents or exterior factors. Fills up with water and causes light bulbs burnout and safety issues. Reports driver’s side headlight to dealer’s service department. Day light went out followed by headlight and signal. Now passenger side is also developing condensations. Called GMC, and dealer. No solution or explanation of why this happens to a year old car.