2021 GMC YUKON Power Train Problems

I live in Alaska. It was -13f. We were out and about and when I tried to leave and back up, the vehicle would not go into reverse. If it hadn’t been for a passing motorist my daughter and I would have been stuck there overnight, in negative temps. I was able to drive it home, in limp mode. Come to find out, it is the valve body on the transmission. That in cold temps the valve body can fail. After some research I found that it is a KNOWN issue with these vehicles and there has even been a “Urgent-Distribute Immediately” Service Update regarding the problem. Urging dealerships to review the VIN’s they have in their possession for the issue. I had the vehicle towed to a shop, where they confirmed the problem was the transmission valve body. They were unable to perform the work as it takes a...

On [XXX] driving to Denver the 52,000 mile yukon started making a clicking sound when accelerating on the interstate. Traction control light came on as well as the check engine light. Low power was noticed and we immediately pulled over as it sounded like it was going to blow up. Towed the vehicle 145 miles where we bought it and the shop confirmed the lifters and 5th cylinder are the issue and that the cams could be damaged. Recommend replacing each side. The car is basically new and under the 60K drive train warranty but about 100 days past the 5 year mark. Terrible timing. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

After noticing a "groaning/moaning" sound from the vehicle when turning sharp at low speeds the vehicle was brought into a dealership to be inspected. After inspection, the mechanic stated that the sound is coming from the rear differential and that it would need to be flushed/cleaned up to three times as a potential correction. If the clean/flush does not correct the issue, they would need to replace the entire rear differential. When asked what happens if the rear differential fails, we were advised that we could experience total failure and lock up. This is a safety issue in that if we are driving and the wheels lock up the potential for collision or major accidents is high. I also understand that the differential is meant to last the life of the vehicle and had 123k miles, the life of the vehicle is far from over. Another issue we are experiencing...

At the time an oil change is needed, there is a warning light that says "low oil pressure and low oil." There also has been a "slipping" of the engine at around 60mph. GMC dealer states it is a torque converter. I am worried that the engine will fail or stall while driving The fuel pump control module has been replaced. Motor is not covered under the current motor recall and taking vehicle to transmission shop to have it checked as well

Clicking/rubbing noise when turning slowly. Rear differential issue diagnosed by dealer.

Electronics- module went out @40,000 brand new car Drive train teal differential went out

While my wife was driving to pickup my son from school, the vehicle was stopped at a stoplight and the engine turned off approximately 1 mile after departing the house. After getting the vehicle towed to the dealership because it wouldn’t start, it was determined by the dealership that the engine was seized. The vehicle has 60,500 miles on it and is driven by a suburban woman and has always had all maintenance done at the dealership. The vehicle is parked in our driveway and there are no signs of oil leaks or anything else that would indicate a potential engine failure. This VIN was not recalled with the larger GMC 6.2L engine failure recall, however other 2021 model years were recalled. Recommend immediate expansion of recall due to the unforeseen engine failure while driving with no previous warning lights (oil or check engine) or other indications prior to seizing....

My vehicle is currently in repair due to a known issue with GM. GM has put out a Technical Service Bulletin 20-NA-038 referencing a "well-known" problem with Cylinder 5 failing in 2021 5.3L and 6.0L engines. However, there has not been a recall. Ironically, there were other vehicles brought to the dealership (Sam Boswell GMC in Enterprise, AL) for the same repair on the same day as my vehicle. I'm hoping to get an initiative started for a recall

Problems with the engine shifting gears stalling delayed or won’t engage hard shifting while it’s in motion something’s going on with the engine we’ve called several and had it serviced times of times to ask them what was going on with it in Newport Oregon you can fill it still when you drive. The problem still is not fixed. It’s been happening since we purchased it took it in right away. we’ve asked if our Vin number has come up for a recall repairs we are worried for safety and are currently parking in the car because the dealership is unable to fix what is wrong with the car. They’re telling us there is something wrong and are aware of the recall and won’t fix the problem dealership refuses to take the car they don’t want it without the recall fixed due to safety concerns. you can definitely fill it...

The contact owns a 2021 GMC Yukon. The contact stated that while accelerating, the vehicle jumped and hesitated while accelerating until the vehicle exceeded 20 - 25 MPH. The contact stated that at 1,500-2500 RPM, the failure recurred. There were no warning lights illuminated. The contact stated that while looking online, the contact discovered information about NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling) with a similar failure. The dealer was contacted, and it was confirmed that the VIN was not included in NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). An appointment was scheduled for the vehicle to be diagnosed. The vehicle was not repaired. The manufacturer was informed of the failure, and it was confirmed that the VIN was not included in NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); because the manufacturing date was 3 months after the date for the vehicles listed under the recall. The...

the electronic solenoid in the valve body failed and it is available for inspection. it was struggling to shift on freeway at speeds of 65 mph and i would lose power. the vehicle was inspected by a gm dealership service man. there were no warning lamps when part started to fail, luckily when I parked the vehicle would not go into gear and then the warning light (check engine light) came on.

A valve in the transmission is sticking causing a loss of power, engine light warnings to flash, and hard gear shifts from park to drive or reverse. First occurred on 5/25/25, went to the dealer service department on 5/26/25. Part still not available and it’s been sitting at the dealership since.

I have again taken my vehicle in for about 8th time trying to get an understanding of why my vehicle vibrates. Again, I was told that the problem could not be duplicated. However, when picking up, I had a discussion with the service manager whom had driven the vehicle as well.. He stated that he felt and heard something from the rear end. I explained that I had the differential fluid change about 2 months ago due to a growling noise when making a left turn. He printed the service bulletin for the differential and put it with my paper. I was told I would receive a call from him the following Monday to bring my truck back in to further investigate because it sounded like the vehicle has a bad rear end. I have not received a call back and have attempted to make contact with service manager twice....

My Denali had no previous problems, I pull out of the driveway and I felt a hard Lunge forward without me pushing the gas. Almost like the car accelerated like a hard jerk. I pulled over because I thought I had been hit by another car. After checking no cars around, I pull back out and I felt it again a hard lunge forward. If someone would have been in front of me I would have hit the car in front of me without even pushing the gas. These GMC are dangerous and can’t trust my vehicle. After getting stranded on the road found out the transmission went out. My suv is now being repaired at GMC at my expense. Only had the vehicle 6 months. Recall the transmission.

Knocking coming from engine, seems like engine failure

The engine and transmission shakes and they say all this normal. Vibration occurs throughout vehicle at idle or driving at any speed. Also, rpm hand slightly moves up and down while idling in park. The vibration is more prominent in 2 and 3 row seats. I have taken it in about 7 or 8 times for the same issue to 4 different dealerships. Only one has actually felt the issue and visually saw the vibration/hop in rear of vehicle. The technician could not determine the problem as GM only allowed a visual inspection. He was not allowed to take anything apart so I am still left with the issue and it is getting worse. In addition, vehicle taken to collision shop to inspect frame, vehicle was within spec. Vehicle is now back at another dealership to address the issue. The only thing that all the dealerships have done is road...

For whatever reason our 2021 GMC Yukon Denali is not listed in the current 2025 GMC motor recall including cams and lifters and accompanying parts. While driving our truck about a mile from the house the vehicle began seizing and shaking (almost as if we had blown several tires); we immediately pulled over and accessed. Called Dealership and had truck towed there immediately. We are told that it needs cams and lifters and that b/c our VIN does not pull up a recall that the repairs will cost ~$9800.

We are back on shop for lifter replacement for the 3rd timeand possibly more once they open the project. Valve springs replaced and lifters.

Valve body failure 72000 miles and warranty ended at 60000

Driving at normal speed when my 2021 Yukon backfired and began to lose power. The check engine light came on. The vehicle would go into reverse and would not get over 20 miles an hour. It has been at a GM repair shop since March 24th waiting on the tranmission valve body. There is no ETA from General Motors on when this part will be available. Could this be associated with the most recent GMC recall of 2021-2024 Cadillac, Chevrolet and GMC vehicles?

I have had major transmission failure in my 2021 GMC Yukon Denali (6.2L V8, 10-speed automatic). The vehicle has approximately 72,000 miles. Recently, a critical internal clip/retainer in the transmission broke loose, sending metal debris throughout the transmission. This catastrophic failure has rendered the vehicle undrivable and requires a complete transmission replacement. Unfortunately, the vehicle is just outside the powertrain warranty, yet I firmly believe this failure is due to a manufacturing/design defect – not normal wear and tear. I purchased this Yukon Denali as a premium, flagship SUV and have maintained it carefully. I expected the transmission to last well beyond 72k miles under normal use. It is disappointing and that a core component failed so early. Not only has this imposed a significant financial burden, but it also undermines my confidence in the vehicle’s safety and reliability for my family. A modern transmission should not self-destruct at this...

The engine needs replaced and GM doesn't have any engines or know when we will get any engines. Evidently this affects numerous 6.2 liter engines that GM made from 2021-2024.

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.

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.

Transmission failure at 72k miles.

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

Rear end locking up still after 3 attempts at repair. Concerned about an accident when the vehicle stops moving in traffic.

Upon cold start vehicle rattles when idling down and growling noise when accelerating upon left or right turns. Also, has constant vibrations with sound of metal rattling at speeds above 30 mph. Forward collision light on without a significant amount of mileage on vehicle. I have taken my vehicle to dealership at least 5 times referencing the vibrations. Growling noise was heard by service advisor last visit October 2024, and he stated it probably were the tires. I advised him that brand new tires were put on vehicle, April 18th 2024, rear vibration has never stopped from time of purchase. I have asked dealership to check drivetrain as it is a know issue for 21 Yukon Denali. Vehicle has not received recall but was manufactured at Arlington plant where the parts of the drive shaft was not properly heated and differential is known for issue upon cold start. Vehicle powertrain...

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...

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.

My vehicle has a message that pops up and says "Service Transmission Now, Unable to Shift Soon". I took my vehicle in to a GM dealership and they did a diagnostics and told me that it needed to be "updated and "rebooted". This was not covered under my power train warranty because it was software. However, the message is stil showing and my vehicle is not shifting, jumping, and not wanting to drive- indicating that the transmission may be going out. This is a safety hazard.

I bought a brand new Yukon Denali in 2021. In 2022 at 12,000 miles, the car was riding extremely rough. It was diagnosed as a transmission issue and the transmission was rebuilt after 90 days in the service department at a GMC dealer. Later in 2022, I started getting low oil lights on the dash. The car was brought back to GMC and I was told that there aren't any leaks evident so nothing was done. This happened repeatedly over the last 2 years, at multiple GMC service departments. No leaks, nothing to see here. Last week, the car started shaking violently while driving, with multiple warning lights appearing on the dash. Finally the car just died and I had it towed to yet another GMC dealership. This time I was told that the bearings, piston rings and lifters were all to blame and the car needed a new engine....

Car started making strange noises in the rear portion and was not driving as it normally would. Proceeded to take the vehicle to a GMC service dept. and was told the rear differential is close to failure and is "shot" and needs to be replaced. The service representative advised us to not drive the vehicle because it is unsafe to operate. Upon investigating it appears there was a recall for 2021 Yukon's for this same issue however this VIN number was not included in the recall but it appears this is the same issue. My vehicle remains at the service center waiting for the "differential assembly" to be replaced but it is currently on backorder and we were given no time frame of when this will be resolved or when the parts will be available.

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.

Out of no where the right side makes a clicking noise when I turn

Hello, I am a Repair Technician for a General Motors dealership in Reno NV. vehicle in question has no ability to to placed in neutral without the engine running. per GM repair guides the vehicle must either be placed in neutral with engine running or a special tool is needed to placed trans into neutral in to move vehicle. this is a major safety concern as vehicle became engine became disabled and the vehicle could not be moved. steering is locked, parking brake automatically sets and neutral position on gear selector cannot be selected. this happened at our dealership. but i can only imagine this happening to someone on the highway. stuck blocking the road with no ability to move the vehicle to safety. i feel this is extremely dangerous and i am sending an email to General motors technical assistance also.

VEHICLE WILL NOT SHIFT INTO GEAR FROM PARK. WHEN IT'S IN GEAR (YOU CAN HOLD THE BUTTON TO SELECT A GEAR TO MOVE), BUT AS SOON AS YOU RELEASE THE BUTTON - IT GOES RIGHT BACK INTO PARK. IT COMES AND GOES. I'VE BEEN STUCK IN MY DRIVEWAY. STUCK AT THE GROCERY STORE. HAD IT ONCE SURPRISE ME AT A STOPLIGHT AND WAS ALMOST REAR ENDED - THAT TIME I NEEDED TO HOLD THE BUTTON TO ESCAPE TO THE NEAREST PARKING LOT. DEALER, OF COURSE, WAS NOT ABLE TO REPLICATE AS THEY SAID THE ISSUE DOES NOT THROW A CODE. I HAVE VIDEO AND PICTURES, WHICH I HAVE SUPPLIED. SOMETIMES THE ENGINE LIGHT COMES ON TOO. DEALERSHIP DID SAY THERE WERE SOME SERVICE NOTES IN THE SYSTEM REGARDING A SIMILAR PROBLEM, BUT THAT GM HAS YET TO ISSUE A TSB. I'M HONESTLY WORRIED THIS WILL CAUSE A MAJOR ACCIDENT AND...