GMC Complaints

I think my vehicle is apart of this recall: March 17, 2014 NHTSA CAMPAIGN NUMBER: 14V118000 Side Impact Air Bags Wiring Connections Failure of the side impact air bags and seat belt pretensioners to deploy in a crash increase the risk of injury to the driver and front seat occupant.

2021 Harley Davidson Sierra 4WD, 6.2L L87. Started the truck in the morning and immediately heard intermittent, very loud banging noise coming from engine. Shut truck down quickly and had it towed to dealer. Diagnosis was bent pushrods & failed lifters which were replaced under warranty. Factory warranty expired only 4 months after this failure, and the recall does not include my VIN so I did not get an extended warranty or any other protection. GM has yet to even reimburse the tow bill. Completely unacceptable for a truck that was well over $100k when new.

After finishing a long drive south, I shut the engine off and a yellow engine code popped on. I connected my computer to it and revealed a P129F code (fuel pump control module). I have noticed that other GMC models have been included in a recall concerning this problem. The 2021 GMC 2500 Denali should be also since it is the same problem. This needs to be covered by the manufacturer since it is a constant problem.

Since I purchased this truck in 2023 brand new as a 2024 the shifting has been very abrasive. It shifts far excessively harder than it should and I have brought this to the dealership’s attention many times. Now I am finding out that there is a massive recall on this vehicle’s transmission because of these issues that have been happening. The error codes are P0700 and P0747 The Engine and Transmission System is not performing as expected. An issue has been detected in the Transmission System that transfers power from the engine to the drive wheels. You may experience reduced power or shifting issues.If the vehicle is continually driven with the check engine light on, the emission controls might not work as well, the vehicle fuel economy might not be as good, and the engine might not run as smoothly. This could lead to future repairs.

The contact owns a 2019 GMC Sierra 3500. The contact stated that while attempting to switch lanes, the side-view cameras failed to operate as needed. The vehicle was taken to a dealer where it was diagnosed with a disconnected wire from the side-view cameras. The wire had poor connection, which caused the cameras to fail due to low voltage. The vehicle was not repaired. The manufacturer was notified of the failure and stated that the part to repair the vehicle was no longer manufactured. The failure mileage was 53,004. The VIN was unavailable.

When I accelerate the vehicle, the gears shifts every 10mph when it shouldn’t. It does it all the way up to 60mph. It has been an on going problem since we got the truck

CORRODED GROUNDING STRAP FAILED CYLINDER 5 GLOW PLUG CIRCUIT CRACKED AND SEPARATED EXHAUST BACKPRESSURE VALVE

My truck is at the dealership for a failed transmission valve body. I was doing some research on this issue and saw recall N242454441. I asked the service writer about this and he said my truck was not covered by the recall. I had all of the same issues as described in the recall. effects can cause harsh shifting, setting a service engine soon message, reduced engine performance or P0747 diagnostic trouble code. I was driving along when the check engine light came on then a message on the dash said reduced power mode. I barely made it to work then called the dealership and told them I was bringing it in if I could make it. When I tried to take it to the dealership the rear wheels seemed to be locked up when in drive but would move in reverse. After coasting forward in neutral then reversing the wheels seemed to unlock in drive but then I didn’t have reverse. I have the same drive train with the 10 speed transmission. I think this recall needs to be expanded to include my truck as well as countless others for this known issue.

The contact owns a 2021 GMC Yukon. The contact stated that while driving at undisclosed speeds, the transmission was shifting hard, with severe vibrations and shuddering. The vehicle was taken to the local mechanic, who confirmed the failure and advised the contact to take the vehicle to the local dealer. The vehicle was taken to the local dealer, and the failure was confirmed, but the vehicle was not repaired. The contact stated that the vehicle was previously serviced under NHTSA Campaign Number: 24V797000 (POWER TRAIN); however, the failure occurred. The manufacturer was notified of the failure, but no assistance was offered. The contact stated that the manufacturer had issued a special coverage associated with the failure but offered no assistance. There was no fault code retrieved associated with the previous software update that was performed under the recall campaign. The failure mileage was 78,000.

While traveling from [XXX] to [XXX] for vacation, I was in [XXX], and when I pulled off the interstate and came to a stop sign the vehicle quit. At first, I was unable to restart the Vehicle, but after sometime I got it started and was able to pull it off the road while the engine was making very loud clattering noise and the vehicle would not stay running. Prior to this there were no warning, lights or indications that the engine was going to quit. I checked the engine oil and it was full. I had the vehicle transported to a GMC dealer in [XXX], where it was diagnosed as requiring a new engine. The vehicle is a 2026 GMC Sierra 1500 Denali purchased in December 2025 and has 8,865 miles on it. A little over 4000 miles I had the vehicle oil changed at Starling GMC Titusville Fl. At the time of my service visit, I asked the service writer, [XXX] to check the engine idle because at times it seemed to run a little rough and it quit while pulling in my driveway one day. [XXX] advised me that there is no idle adjustment on the vehicle, so I said I’ll just keep an eye on it. There were never any indications of an engine problem prior to this or even as of now there are no warnings displayed on the instrument panel. I also subscribe to onstar and it indicates everything in the vehicle is normal with no issues. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)