Home · 2021 GMC Yukon Denali Xl 1500 · Complaints

What 295 owners told NHTSA about the 2021 GMC Yukon Denali Xl 1500

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (295)Crash / fire / injury (9)Engine (156)Fuel system (52)Transmission & drivetrain (47)Engine & cooling (29)Electrical system (26)Airbags (18)Driver assistance (18)Steering (11)Brakes (7)Seats (6)

156 of 295 complaints match · Engine · clear filters · page 6 of 7

Jan 27, 2025Engine

The contact owns a 2021 GMC Yukon. The contact stated that while driving at 60 MPH, the vehicle's engine shut off without warning. The contact was unable to start the vehicle and was left stranded on the roadway for hours. The contact finally managed to have the vehicle towed to a dealer where they diagnosed the vehicle with a defective engine main bearing(engine failure). The vehicle remained in the dealer's possession where it had yet to be repaired. The manufacturer was notified of the failure but offered no assistance. The failure mileage was 28,450.

NHTSA ODI 11638715

Jan 23, 2025EngineFuel system

My family and I found ourselves stranded on the interstate when our engine failed while we were driving on I-10 at 75 mph. The connecting rod bearing got lodged in the engine, causing it to seize. This put us in an extremely dangerous situation. I believe these vehicles should be recalled. I've been in discussions with GM to buy back the vehicle, but their leadership has declined my request. They are offering to replace the engine, but I do not want this vehicle back.

NHTSA ODI 11638168

Jan 22, 2025Engine

At approximately 14,000 miles my 6.2L V8 engine had a lifter go bad on the truck. GMC covered this with warranty at the time. The truck seemed to perform well until I hit approximately 94,841 miles and then a lifter went bad again. I had an 85,000 warranty and this repair was not covered. I was quoted $6,500 to repair the truck by the dealer. I made a social media post and tagged GMC. GMC reached out to me directly and took $1,000 off of the repair and I paid $5,576.48 out of pocket to repair the lifters. GMC also offered an extended 2 year warranty on the engine at that point that is expires in September of 2025. I currently have 143,000 miles on the truck and my intent was to drive this truck for as long as humanly possible. I was told that this was designed to be a 500,000 mile truck. My engine is now burning approximately 2.5 to 3.5 quarts of oil between oil changes and I'm worried that there is something else wrong with the engine and that another lifter will go bad. I love my truck and can't afford another $6,500 to $10,000 repair. I sometimes get this car and other cars serviced for an oil change at the Mavis Auto in my neighborhood and the shop director who has been in the business has a friend who is a mechanic with GMC and he told me that his friend was given directive that if one lifter went bad 100% of the lifters, the housing and CAM shafts were to be replaced. (I'm not a mechanic so I may be missing some details here) Anyway - I've been informed about the NHTSA Investigation Into the V8 Engine in my truck which has opened my eyes to other mechanical defects associated with my truck. I'd like to make this report to protect myself and my investment. I do not want incur additional expenses related to manufacturer defects and I do not want to feel unsafe on the road with this vehicle.

NHTSA ODI 11637675

Jan 20, 2025Transmission & drivetrainEngine

The motor on my 2021 Yukon completely failed while driving on a busy state road. The blown motor was replaced by a local GMC dealership, so I do not know it's status or if it'd be available to inspect. My safety was greatly put at risk. I am blessed that my wife and children were not with me, if they were, I would be even more furious. While driving on a busy state road, the tachometer dropped to zero and the truck automatically shifted into neutral. I quickly realized the engine had shutdown, and attempted a restart while coasting. The motor would not restart and I was lucky enough to coast into a nearby parking lot. Had I been in traffic, on the highway, or at a stop light, the situation could have been even more dangerous. As it was, I was stuck in below freezing temps for several hours waiting for triple A. They sent the wrong tow truck twice, and I eventually cancelled the triple A call and called a local wrecking company to come tow the car more than 24 hours later...luckily in the interim I was picked up by a family member. The issue was simply stated to me by the mechanics at the local GMC shop as the motor had "blown", they didn't know why, and they completely minimized the magnitude of the situation. To the best of my knowledge the blown engine has only been looked at by GMC employees. There were NO warning lamps or other symptoms associated with any such failure of this type - which in my opinion, makes the matter even worse and more dangerous. I am frankly furious that GMC is not doing more to address these known catastrophic issues. They have said they will not extend the powertrain warranty and I've read online that people have had their "new" motors blow the same way that the old ones did.

NHTSA ODI 11637103

Jan 19, 2025EngineFuel system

My 2021 Yukon Denali has roughly 70k miles and this is now the SECOND time that my engine shut off while driving >55mph on the interstate in the past 3 months. The first time, I had the sensation that the car was running out of gas when I went to accelerate. After about 5-10 seconds, the engine turned off, but the electronics stayed on. I coasted to the side of the road and tried multiple times to start it without success. The engine sounded fine while turning over and over, but it would never start. That episode turned out to be a bad fuel pump control module, and after roughly $400 at the local Firestone auto repair shop, I was on my way (FYI, they didn't diagnose it; I learned that was the likely problem by reading online forums and basically demanded they replace the FPCM). Now, here I am about 3 months later, and it happened again, just two days after I had the vehicle serviced at the GMC dealership for a check engine light that was intermittently coming on. The technicians said I needed an update to the Engine Control Module which was completed. The main difference was that this time, I had zero warning. There was no sensation of running out of fuel or funny noises from the engine. I just went to give it gas and noticed it wasn't working. There was a warning on the dash saying push button to start the vehicle (once again, the electronics stayed on when the engine shut off). After coasting to the side of the road, the battery seemed to be good, but the engine wouldn't turn over. I had it towed to the shop and am being told I will likely need a new engine!

NHTSA ODI 11636897

Jan 18, 2025Engine

In July of 2024 while coming back from vacation pulling our boat our 2021 Yukon Denali with 6.2L motor started making noise while traveling on the interstate. I started to get over to the shoulder as the car lost power. I finally got it over to the shoulder as traffic was heavy and it was pouring down rain. As soon as I got it to the side of the road the check engine light came on and the engine died. It would not turn over or restart. After about 3 hours along side the very busy highway in bad weather GM finally sent a tow truck to take it to the dealer. After a week in a half it was finally diagnosed with spun rod bearings and main crankshaft bearings. The car had just over 21,000 miles and had been serviced per the manufactures recommendations. It took over 7 weeks for the car to be repaired where they replaced the engine with a remanufactured engine. We did not get a loaner car since it happened in KY and we live in IN. Our family had to find our own way home and a way to get our boat home also. We then had to find our own way back to get the vehicle once it was repaired. GM did reimburse us for a rental car at $44 a day only and they did not pay any taxes or fees only the rental rate. You cannot rent a similar sized vehicle for $44 dollars a day. We spent approx. $2K out of our own pocket for expenses related to this breakdown. The vehicle now has approx. 29,000 miles on it and we have not had any problems since we got it back

NHTSA ODI 11636742

Jan 5, 2025Engine

I was driving on the highway at about 70 miles an hour and my vehicle started to decelerate without warning, dash lights came on. I was able to safely get off to the side of the road. The vehicle would not start, so I had to call a tow truck. Once towed to the GMC dealership and looked at by mechanics, I was told the engine failed and I would need to replace it. I was also told there were metal shavings in the oil. My vehicle did this without any warnings. I never had the check engine light come on before this incident, nor were there any noises that would make me think something was wrong with my vehicle.

NHTSA ODI 11634169

Dec 2, 2024Engine

While accelerating the vehicle began to make an audible liquid grinding sound and three error codes popped up, one after another. The engine light began to flash, however the vehicle kept moving. I limped roughly .5 mile to the closest service station where I subsequently had my vehicle towed to the dealership where it was purchased. Later notified the lifter and CAM failed. Mind you, this vehicle currently has 55,000 miles and has already had the transmission replaced at 45,000 miles due to metal flake in the transmission because of a faulty hose from GM. While I appreciate the dealership ordering a new engine for me, I do not feel safe driving this vehicle, and do not feel it should be resold to anyone given the MAJOR safety issues associated.

NHTSA ODI 11628371

Nov 22, 2024Transmission & drivetrainEngine

The contact owns a 2021 GMC Yukon. The contact stated while driving 60 MPH, the message "Reduced Acceleration" was displayed, and the check engine warning light illuminated. The contact stated that the vehicle failed to exceed 40 MPH, and the vehicle was driven back to the residence. The vehicle was taken to BMI Automotive transmission shop, where the valve body and the intermittent speed sensor were replaced; however, the failure recurred while driving. The contact was able to drive to the residence. An unknown dealer was notified of the failure. The vehicle was in the process of being towed to the dealer. The vehicle was not yet repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 56,500.

NHTSA ODI 11626922

Nov 21, 2024Engine

I was driving 55 mph and the engine failed without any prior warning. I was partially blocking traffic while waiting for a tow truck. The car was taken to a repair facility and diagnosed. Spun rod bearings on cylinders 1 and 2 damaged the crankshaft. I purchased this car $49,000 45 days ago and have made one payment on a car that is not drivable and parts are not readily available. There is a GM service bulletin because this is a known issue but not a recall. The power train warranty is up by mileage not time. I contacted the dealership and GMC and they will not assist with repairs.

NHTSA ODI 11626737

Oct 8, 2024Electrical systemEngine

While on a red light and foot on the break, the car turned off completely and would not turn back on after many tries. Truck was towed but mechanic did not find any issues with vehicle as he turned it on with no issues. All lights flashed and indicated battery was low but was not warned prior. The previous week, the truck shut off completely as well but it turned on quickly.

NHTSA ODI 11618694

Sep 2, 2024Engine

[XXX] on [XXX] Yukon stalled mid-drive as we exited [XXX] toward [XXX] . This is the SECOND stall on this Yukon. I had reported the first stall on June 04-2024 [11594097]. This time it would not start at all, and locked into P. There was a strange noise coming from the engine when we were on [XXX].We were going 65mph. My husband told me to start recording a video so that we can capture the noise, within 1-min as we started to exit on [XXX] towards Wake Forest, the sound was getting louder, the car started shaking as we started to slow down towards the entrance to [XXX], the engine cut-off. It smelled like burning, there was no smoke but the smell was strong.  It would not start after multiple attempts, it would not shift it locked on P. At this point, the ENGINE LIGHT went on! Electric was still on, air conditioning turned off, no messages on the dashboard. The only warning was a metal like rubbing coming from the engine. I will upload this 16-min video to TikTok as a multipart series, since my multiple complaints have been falling on deaf ears! We called Gm Roadside for a  tow, they said to call 911. We called 911 about 4 times and they did not have anyone to come. Gm roadside assistance could not get AAA to come until 9:45pm. AAA called us around 9:40 informing us that the available tow cannot move this Yukon because it would not shift gear to N and it will require a specific tow truck. We called back GM roadside about 5 times, just run around with no solution and a lot of attitude and lack of concern! Finally the Raleigh police Supervisor arrived, minutes later a State trooper offered assistance. They wanted the car off the road, GM was still on the phone and put them on speaker with the officer. Finally the office requested their tow as GM FAILED to get a compatible tow truck, we paid out of pocket, CASH! The Police drove us home around 11:30pm! GM DID not have contracted equipment for their OWN Trucks! New lows for GM! Incredible! POST COVID INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11612079

May 26, 2024EngineFuel system

Twice in a five day span vehicle stalled out, acting like it is not getting fuel. Each time it took several minutes of trying to restart and getting below fuel tank to give it a couple knocks to get it to start. Both times there was atleast a half tank of gas. Each time the car was running well when it suddenly slowed down on its own, the first time I was on a busy street resulting in the need for a tow and I had my grand baby with me. The second time it was an isolated road and surprisingly I had cell service to call for assistance. The tow truck driver told me he thought it was the fuel pump. I looked up my vin but it isn’t listed as one of the affected vehicles in the GMC Yukon recall, however it certainly seems like it is. I had no warning of any type with each incident, the car simply acted as if it ran out of gas. I have an appointment with a local garage. Additionally when this happens the vehicle does not let me shut it off. The engine isn’t running but I can’t power down the electronics system.

NHTSA ODI 11590797

Mar 30, 2024Engine

Total engine failure due to bearing issues in the bottom half of the engine.

NHTSA ODI 11580224

Feb 2, 2024Electrical systemEngineFuel system

FUEL PUMP POWER CONTROL MODULE SKU NUMBER 13537053 brand new GMC denali less than 9000 miles had serviced for 5 previous recalls drove for a week. Truck completely shut down on road no power will cause serious or death if person is on highway as engine turns off and car shuts down due to electric shift cant put car in neutral not even with key from key fob so if get vehicle towed cant even shift into neutral big fail on gm part and will cause major issues as vehicle just shuts off do to this issue no service light. Major accident waiting to habit and back ordered parts on a expensive machine

NHTSA ODI 11569524

Jan 22, 2024Engine

My family and I purchased this vehicle brand new in August 2021. We live in Phoenix Arizona and bought it from Earnhardt Buick & GMA in Mesa, AZ. While driving the vehicle in the last few weeks I personally could smell a strong odor of fumes in the cabin when the A/C or Heater were on. After a few days of noticing it my nose got numb to the odor as I dismissed it and kept driving the vehicle. After about a week, I had my two kids in the vehicle, they both noticed and made comments on how strong the odor of fumes were. We decided to not utilize the A/C or the Heater and contacted the dealer for investigation and repairs. This is a very serious health hazard as I and my family were exposed to exhaust fumes entering the cabin. For a few days and nights I suffered headaches and some dizziness as I was driving mostly the vehicle. We did take it to Earnhardt Buick & GMA in Mesa, AZ for investigation and repair. The maintenance supervisor confirmed that indeed somehow the exhaust had some crack that allowed fumes to enter the ventilation system. The Vehicle is now under repair at the dealership. I was notified by the maintenance advisor that this defect would not be cover under warranty as the vehicle is out of manufacture warranty. I Also had purchased an extended warranty (Platinum) which they had stated "bumper to bumper", but this also does not cover the manufactures defect. There were no warning lights associated with this problem. I would strongly recommend that inspections be made, especially if some drivers have problem with smell and odors. This is a big health hazard. Thank you for your attention. [XXX] . [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11567126

Jan 9, 2024Fuel systemTransmission & drivetrainEngine

The contact owns a 2021 GMC Yukon. The contact stated while driving 25 MPH, upon accelerating from a light, the vehicle began to shake and decelerated and failed to accelerate and exceed 25 MPH. The vehicle accelerated, jerked, and stalled. The check engine warning light was illuminated. The vehicle was taken to the local dealer, where it was diagnosed that the fuel pump control module needed to be replaced. The mechanic informed the contact that the parts were on backorder. The vehicle was not repaired. The contact stated that the failure was related to NHTSA Campaign Number: 21V739000 (Fuel System, Gasoline). The manufacturer was notified of the failure and opened a case. The failure mileage was approximately 67,150.

NHTSA ODI 11564320

Nov 27, 2023Engine

On Monday, November 20, 2023, I was operating my vehicle on Interstate 80 in western Nebraska when suddenly and without any notice, apparently an engine lifter in cylinder 8 failed causing the vehicle to lose power while in heavy semi-truck traffic, while operating at approximately 80 mph, forcing me to avoid a collision. Since the incident, I have become aware that this is a known problem with GMC, and that they have extended their power train warranty under certain circumstances because so many engine lifters are failing, many without notice or warning. My vehicle is serviced every 6,000 miles at a GM dealer and also operates the OnStar system. Neither the dealer nor OnStar detected the failure or warned me of any issues that cause a stall while in traffic. Fortunately, I am an experienced driver and was able to safely pull the vehicle off the highway.

NHTSA ODI 11557027

Nov 21, 2023EngineFuel system

While traveling on the interstate at 70 mph with husband and child inside, the vehicle started shaking and stalled. Had to glide off onto an exit ramp where the vehicle stopped and would not restart. Onstar ran diagnostics and came back with code P129F.

NHTSA ODI 11556380

Sep 21, 2023SteeringBrakesEngine

This GMC Yukon underwent an over the air update in remote Wyoming and was almost undriveable due to steering problems and brake malfunction. Also engine and transmission problems. It has been awaiting repair, but I have been informed that no fix is available because of transmission defect. No parts available We were nearly stranded.

NHTSA ODI 11545764

May 10, 2023AirbagsEngine

My transmission had to be replaced back in December of 2021, and now I have taken my truck back to the dealership for transmission problems again, the transmission is slipping again, driving rough and now im getting a safety restraints message and the airbag picture is coming on

NHTSA ODI 11521401

Mar 20, 2023EngineSpeed control

The contact owns a 2021 GMC Yukon. The contact stated while stopped at a traffic signal, the engine started revving without the accelerator pedal being depressed. The contact stated that the vehicle occasionally independently accelerated. The contact state that the failure also occurred while the vehicle was in park(P). The contact stated no warning light was illuminated. The contact had not taken the vehicle to a local dealer or independent mechanic. The vehicle had not been diagnosed or repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 17,000.

NHTSA ODI 11512883

Oct 27, 2022Engine & coolingEngine

The contact owns a 2021 GMC Yukon. The contact stated that while driving approximately 30 MPH and accelerating to approximately 40 MPH, another vehicle suddenly pulled in front causing the contact to apply the brakes. While attempting to apply the brakes, the brake pedal went to the floor. The traction control, ABS, ECF, and check engine warning lights were illuminated. The contact then pulled over to the side of the road where the vehicle eventually coasted to a stop. The contact drove the vehicle slowly to the residence. The contact had the vehicle towed to the dealer who diagnosed that the brake master cylinder and ECF needed to be replaced. The vehicle had not been repaired. The manufacturer was made aware of the failure and opened a case. The approximate failure mileage was 24,000.

NHTSA ODI 11491107

Sep 9, 2022Engine

Total Engine Failure. Cause UNKNOWN, Driving on highway from family vacation. For 1-2 miles prior to incident car begins running rough, High RPMs, Engine pressure rising. Receive a warning on dash. 'Engine shutting down. No prior warnings or issues in the vehicle life. Pull over' Engine will not restart. Have to call two tow drivers, neither are able to get engine into neutral to tow. Second tow driver uses makeshift skids to pull car onto tow truck. Is towed to nearest GMC dealer. At next business day the car is inspected and prognosis is total engine failure. This was a 2021 just over a year old with 22,000 miles. Vehicle shut down every person in vehicle could have been injured if we had been unable to pull over to a safe location, were driving 70mph on highway.

NHTSA ODI 11483754

Aug 2, 2022EngineFuel system

On a road trip out of state we stopped for gas. We got back on the road and few miles out the car suddenly slowed and gave a message on the screen something about acceleration. We pulled over and next the reverse didn’t work. We stayed overnight then next day the reverse still did not work. We were able to place in drive and continue on but we don’t have fully functioning reverse mode.

NHTSA ODI 11477200

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Working with the data? Download all 295 complaints as CSV · fetched from NHTSA July 25, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2021 GMC Yukon Denali Xl 1500 verdict →