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

Transmission valve body (transmission control unit) failure at 72,000 miles. This is the 10-Speed transmission that is the subject of several other recalls for diesel versions of the GMC Yukon. No warning lights, and potential for rear wheel lock up.

NHTSA ODI 11654553

I was driving down the interstate traveling 75 mph and with any warning the vehicle shifted into neutral. I made my way to the side of the interstate with any ability to accelerate on a busy stretch of highway. I had my children in the car with me. After making my way off the road, I shifted car to park and it wouldn’t go back into drive. I turned the car off, in an effort to put the car back into drive. The car wouldn’t not restart. We were stranded in the side of the interstate 6 hours from home. I had the vehicle towed to Ed Morse GMC in Rolla, MO. The let me know after a few days that my vehicle needed a new engine and that this has been an issue with other 2021 GMC Tahoe vehicles. We decided to have the vehicle towed to Bob Howard GMC in our town, Edmond, OK, and they confirmed a new engine was needed. In all we had to replace the engine, radiator, cooler lines and fuse array. There were zero messages or warnings leading up to this event. This was very u expected, scary and u safe for not just my family in my vehicle, but all the vehicles around my that day on the interstate.

NHTSA ODI 11654594

The vehicle was handed off to the dealer for a routine oil change and transmission flush. The dealer stated over the phone that during the engine's oil draining process, the tech noticed metal particulates in the oil. The oil was allowed to completely drain until no drips fell from the drain plug. The tech then filled the engine with new oil to the correct level. After the trans flush was complete, the tech took the vehicle for a test drive, during which they noticed strange engine noises. The tech then parked the vehicle in the garage bay, where the engine subsequently failed. What component or system failed or malfunctioned, and is it available for inspection upon request?: The dealer has not confirmed the exact cause of the failure, however it is expected to be because of a failed connecting rod bearing. The NHTSA may contact the dealership for information regarding an inspection. The dealer is Koons Chevrolet Buick GMC in Clarksville, MD 21029. How was your safety or the safety of others put at risk?: UNKNOWN, vehicle was parked at the time of failure Has the problem been reproduced or confirmed by a dealer or independent service center? : UNKNOWN, There are many forums online in which people have stated similar issues. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others?: UNKNOWN Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear?: UNKNOWN

NHTSA ODI 11654304

I was passing a semi truck at 80 mph on the highway, after passing I tried to reduce my speed on the cruise control but got no response from my vehicle. I pulled off the highway and the engine was dead. I feel lucky to be alive the truckers were whizzing by at 80mph while we waited for a tow truck. The dealer has confirmed the engine is seized. There were no warning lights or other symptoms.

NHTSA ODI 11654160

Engin failure

NHTSA ODI 11654161

I was driving my vehicle at a speed of around 50 MPH when the vehicle had an sudden loss of power. The vehicle displayed press the start button while the vehicle was still moving with the motor off. I pressed the start button and the vehicle shifted to park and went to complete loss of power functions. The hazard lights would not work, the vehicle would not start or move out of park. The vehicle was stuck in the fast lane in park with no way of moving it or warning others with hazard lights. My daughter and I almost got hit by a semi due to the vehicle issues. I had to call 911 to get police there for safety concerns and a tow truck to take the vehicle back to the dealership. The tow truck couldn't get the vehicle out of park as well, so he had to drag my vehicle onto the tow truck. I have a 2021 Yukon Denali with the 6.2 engine. The dealership told me I need a new engine because of a known failure with the engine. They can't promise me replacing the engine will fix the issue. The vehicle has less then 60,000 miles on it. This engine issue put my life and my daughters life in danger. I had to carry my daughter across the highway because it was unsafe to stay in the vehicle. I can only imagine what could of happened if we were traveling at higher speeds with no way to exit the vehicle. The dealership told me it is going to be 3 to 4 months before I get my vehicle back and they can't promise the new engine won't do the same thing. This is a huge safety concern that GMC needs to address. I am stuck paying for a vehicle that puts my family in danger. Something needs to be done immediately. The dealership told me they have several Yukons in the shop with the same issue waiting for an engine replacement.

NHTSA ODI 11653187

I started the 2021 Yukon Denali this morning and there was a slight squeaking noise coming from the front of the car. I began driving and the noise went away. I parked the car and completed an errand. I then started the car to return home and on the way it started making the noise but much louder. I pulled over and the car died and refused to start. GMC Roadside Assistance sent two different tow truck that were not able to tow the car. Tow Truck #1 - Flatbed truck. Car did not go in to neutral because it couldn't start so the driver said that he was unable to pull it up onto the flatbed. Tow Truck #2 - Tow truck w/ Dolly wheels. Driver said it was too heavy for his Dolly to tow the Denali. GMC Roadside Assistance then said that they're two trucks were unable to pickup the Denali and that I was on my own to call and get a tow truck and they would reimburse me. I am on the side of the road all morning not knowing what tow truck company nor what type of tow truck to ask for...... Denali still does not start and am now awaiting a local tow company to make the pickup. GMC Roadside Assistance was a total failure.

NHTSA ODI 11652591

The car is by hard shifting. The dealership found, “THE TRANS TO HAVE A SHUDDER AND DEBRIS IN THE TRANS FLUID INDICATING TORQUE CONVERTER FAILURE RECOMMEND REPLACING TRANS DUE TO TORQUE CONVERTER FAILURE SENDING DEBRIS THROUGH THE PUMP AND VALVE BODY.” The first time we brought the vehicle into the dealership they just replaced the fluid and didn’t inspect for failures. The dealership now did and if the torque converter fails the car won’t drive, if I’m on the freeway that could cause a crash or worse.

NHTSA ODI 11652675

One bank of lifters went out while under warranty and were repaired then the other ones went out shortly there after.

NHTSA ODI 11652021

Was driving normal down interstate. Interstate has two barrie walls making it a two lane road with no shoulders. Car was almost rear ended 3 times while it was stopped in middle of interstate. Me, my husband, my [XXX] , [XXX] and [XXX] were all in the car. I had to jump out the car while it was still rolling to make sure my children made it to safety before someone didn’t see us and hit us at 70mph. We had to cross the road and jump over a barrier in the construction zone. It took our high way patrol 35 mins just to show up and shut the road down to get the vehicle moved. According to the GM mechanic, a rod went through the block causing a hole. There was no warning of this happening, the car made noise and the vehicle automatically said low oil pressure, shut vehicle off, then an instant pop and smoked everywhere. The motor is on back order and won’t be able to be replaced for over 6 months if that. We had just purchased the vehicle and the motor was blown not even 3 hours after owning it. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11651697

My vehicle showing service safety restraint system and airbag light . When check with dealer code b14dc has appeared ( Driver inboard seat side air bag high control).

NHTSA ODI 11651383

The valves, the pistons had to be replaced. The motor went out. The motor should be replaced but they did not give me that option. The vehicle only has 50K on it. Was kept in the garage. Had regular maintenance. The GM service garage has had this vehicle since 2-11-25.

NHTSA ODI 11650696

Had unexpected loss of engine power, rough idle and warning lights. Has been out of service in the GMC dealer for almost 6 weeks to date. No diagnosis. No repair date. No response from GM other than "waiting on diagnosis" No loaner or rental provided. Still under warranty. 6.2 v8. Engine failure suspected. I am reporting this to help switch the investigation to an actual recall of the wide-spread issue with this engine. No documentation written information provided by GM.

NHTSA ODI 11650578

Transmission failure at 72k miles.

NHTSA ODI 11650238

Engine locked up, local gmc dealer diagnosis " engine is locked up - metal debris in oil - failed internal components". Engine made a few noises the week before, no other warning signs. Vehicle died in the turning lane of a two lane road. One hour not moving in busy traffic until tow truck arrived

NHTSA ODI 11649957

Vehicle engine stalled while driving in school parking lot. Safety concern as car when from “R” to “N” while backing up (2x). Engine would not turn on afterwards. Vehicle code P129F showed trouble with fuel pump power flow control module.

NHTSA ODI 11648808

Main Value body goes out when it wants to in the Transmission . no replacement parts available . Been 6 week , When this value goes out while go down the highway there is no pull to the wheels

NHTSA ODI 11647800

The contact owns a 2021 GMC Yukon. The contact stated that while his wife was driving at an undisclosed speed, the vehicle lost automotive power. The Electronic Stability Control warning light was intermittently illuminated. The vehicle was towed to a local independent mechanic where it was diagnosed with a spun rod bearing failure; however, further investigation was needed. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 102,000.

NHTSA ODI 11647571

The component that failed was the Camshaft and Lifters in the Engine - My safety and others was put at risk because while going 45mph, I suddenly lost forward moving power and couldn't go faster than 35 - braking power was sketchy and only responsive when pumped. - I received the following errors on my dash "Service ESC" "Service Traction Control", Reduced Acceleration Drive with Care", "Forward Collision System Unavailable", "Service Emission System" the vehicle would shudder violently- this problem has been confirmed and corrected at a huge expense (see bill) -

NHTSA ODI 11647336

The contact owns a 2021 GMC Yukon. The contact stated that upon his wife attempting to start the vehicle, the vehicle failed to start as intended. The contact's wife stated that she had previously heard an abnormal rattling sound coming from the engine compartment in the days prior to the failure. No warning lights were illuminated. The vehicle was towed to the dealer, who diagnosed a failure with the oil pump, resulting in damages to the engine. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact stated that there had been a partial engine rebuild performed on the vehicle several months prior to the failure. The manufacturer was not notified of the failure. The failure mileage was 140,000.

NHTSA ODI 11646769

What component or system failed or malfunctioned, and is it available for inspection upon request? - Engine Failure, on November 8, not certain engine is available for inspection -2nd Engine Failure, February 27, engine being replaced now and can be inspected How was your safety or the safety of others put at risk? -first engine failure happened on highway interchange without warning and stranded the vehicle on a busy highway with 6 passengers (5 of them children) at risk -second engine failed in the middle of an unprotected intersection, and would have caused an accident if other drivers were unable to brake Has the problem been reproduced or confirmed by a dealer or independent service center? -both engines discovered metal debris in the oil pan Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? -yes, vehicle was inspected by GMC dealership both times Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? -no warning lamps appeared, a message was displayed to restart engine as the engine was shut down while in Drive.

NHTSA ODI 11646087

at 60860 my first engine went out General Motors offered no help i have extended warranty it took 3 months to get my Yukon back now 40000 later 2nd engine goes out cannot get a dealer to touch excuse after excuse tried to contact General Motors nobody will talk to me

NHTSA ODI 11645579

Motor blew up

NHTSA ODI 11645437

Engine or something is making a noise every time turned on and now while turning off

NHTSA ODI 11645453

Hello, I am writing this complaint because i bought this 2021 GMC Yukon new from King GMC in Loveland CO. The engine seized up on me while driving once turned off, i was able to get it going and now it has done it again but this time no luck getting it going, Maintenace has always been maintained and up kept, and the more i read about this i am finding out its a problem that everyone is getting with this 6.2 litter engines. The dealer wants to charge me 30k to change the engine and radiator and cooler lines on an already ridiculous overpriced vehicle. I am not sure why there hasn't been a recall issued perhaps because it involves a new engine? over700k people have the same problem. if thier is something you guys can do i dont think its correct the customers have to pay the dues on an unsafe bad design engine. Thank you for your time

NHTSA ODI 11645019