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 warranty is due to expire August 2025 or 60,045 mileage. Therefore with that, the vehicle was placed in service August 2020 months before unproperly heated driveshaft recall was determined. My vehicle should be on the list for this recall as GMC noted this to have occurred on vehicle prior to 07/2021. In addition, a chirping noise comes from front of vehicle while idling and when automatic stop starts back up.There are already known recalls for two of issues noted above.

- Fort Valley , GA, USA

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.

- Storrs Mansfield, CT, USA

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.

- Buchanan, GA, USA

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.

- Lake Charles, LA, USA

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. Of course, now the car is out of warranty. GMC needs to remedy the engine issues in the 2021 models. There are MANY reports of this happening with this engine.

- Waxhaw, Nc 28173, AL, USA

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.

- Midland City, AL, USA

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.

- Elkton, MD, USA

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

- Southfield, MI, USA

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.

- Reno, NV, USA

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 I don't trust having my family in the car. It's an $86,000 SUV. Unreal and so disappointing.

- Berkley, MI, USA