GMC Complaints

I remote started my truck, and when I got to it there was smoke and a flame coming from the rear power window. The remote start activates the rear defrosters, which started the electrical issues. I shut off the engine, and a loud pop followed, which was the shattering of the driver side rear window. The flame went out, and could have easily ignited the tarp covering the truck bed. There were no warnings on the console for the issue, and no recalls available. I have seen similar recall, but in a different state and back in 2022. This leaves me with a shattered window in the back, which is unsafe for visibility, and a bill to pay due to manufacturing errors for a feature in the truck. The rear window is all melted, and the glass is chipping away.

The contact owns a 2026 GMC Sierra 1500. The contact stated that after purchasing the vehicle, there was no Owner’s Manual in the vehicle. The contact inquired about the Owner’s Manual and was informed by the dealer that an Owner’s Manual was no longer printed. The contact checked online and became aware of FMVSS 225, which was related to the Owner’s Manuals for similar vehicles. The contact researched NHTSA Campaign Number: 25V815000 (Equipment), addressing the lack of an Owner’s Manual for 2026 Chevrolet Silverado 1500, 2500, and 3500 vehicles. The manufacturer was not notified of the issue.

While driving on the interstate the top part of the grill flew off into following traffic.

At approximately 29,000 miles, my 2023 GMC Sierra 1500 experienced a transmission failure. The transmission began slipping, shifting improperly, and operating unpredictably during normal driving conditions. This occurred without warning and well below the expected lifespan of a transmission, indicating a serious defect rather than normal wear or maintenance-related issues. The vehicle became unreliable and unsafe to operate, particularly during acceleration and highway driving, where delayed or improper shifting created a potential safety hazard. I relied on this vehicle for daily transportation and work, and the worsening transmission condition made continued operation unsafe and impractical. I later became aware that transmission failures are a widespread and documented issue affecting this model year GMC Sierra 1500, suggesting a possible manufacturing or design defect. Due to the severity and premature nature of this transmission failure, I was forced to return the vehicle early. General Motors is now charging me a balance of over $10,000 related to the early lease termination, which was directly caused by this defective transmission and not by customer misuse or negligence. My requested resolution is for General Motors to waive the full balance of over $10,000, as this financial obligation resulted solely from a premature transmission failure caused by a defect outside of my control.

coolant control valve failed, truck cannot be driven due to overheating, Dealer has said due the national backorder, it could be 2 months before they receive the replacement part. There is a significant national backorder on the engine coolant flow control valve for 2020–2025 GMC Sierra and Chevrolet Silverado trucks equipped with the 3.0L Duramax (LM2/LZ0) diesel engine. Many owners are reporting wait times of several weeks to months, with some vehicles sitting in repair shops for over 70 days.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed, and the brakes seized. No warning lights were illuminated. The contact parked the vehicle. The contact inspected the vehicle; however, the failure reoccurred. The contact attempted to drive the vehicle several times, but the failure reoccurred. The contact stated that the failure was persistent. Due to the failures, the contact was almost in two crashes. The vehicle was towed to an independent mechanic, where it was diagnosed with a brake module reset. The independent mechanic contacted the dealer and was informed that the brake module needed to be reset. The technician from the dealer installed the software for the brake module reset, and the vehicle was repaired. The vehicle was retrieved, but the failure reoccurred a month later. The vehicle was towed to the dealer, and the contact was informed that the vehicle needed to be inspected by the engineer. The vehicle was not diagnosed or repaired. The contact was advised to continue driving the vehicle. The contact was advised to disable all the safety features. The contact stated that two major crashes were averted and refused to drive the vehicle until it was repaired. The contact stated that the failure was common with the vehicle. The manufacturer was made aware of the failure, and a case was filed. The failure mileage was approximately 68,000.

On January 24, 2026, my wife was driving the vehicle we purchased in May 2025 from Ziegler GMC in Lincolnwood, Illinois. While traveling on the highway in WI the vehicle suddenly lost power without warning. She was traveling with our [XXX] son at the time and was able to safely maneuver the vehicle off the highway onto an exit ramp. Despite multiple attempts, the vehicle would not restart. She contacted me and arranged for a tow. We waited approximately four hours for roadside assistance before the vehicle was towed to the nearest GMC dealership, located roughly one mile from where the breakdown occurred. Several days later, the dealership completed diagnostics and informed us that the engine required full replacement. At that time, no replacement vehicle was provided. Approximately one week later, we were finally issued a loaner vehicle. As of today, the vehicle has remained in the shop continuously since January 24. On February 23, we were informed that the necessary parts had only just arrived. There is still no estimated completion date for the repair. The vehicle is covered under both the manufacturer’s warranty and an extended warranty. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On Febuary 14 2026 I was driving on the feeder of the freeway with speeds of 50 mph my car suddenly down shifted in the middle of driving started shaking real bad stalled wouldn’t start wouldn’t go in gear at all would just die and say engine power reduced. This is after it had just been at the dealership and they said all I needed was an update. It had to be towed and the dealership said it was my high pressure fuel pump had failed. They replaced it and gave me the car back. I staled the next morning going to work on the freeway going 70 mph same exact thing happened except this time I could smell gas so strongly. I had to sit on the side of the highway until it was picked up due to gas smell and fear of fire. They say a bolt broke off of the high pressure fuel pump they just installed

The contact owns a 2021 GMC Yukon XL. The contact stated that while his wife was driving approximately 30 MPH, the vehicle started to lose motive power with the message "Service Transmission Now" displayed. The driver was unable to shift the vehicle into reverse(R) and turned around and returned to the residence. The contact and his wife researched online and found that there was a recall for the transmission for the year and model under NHTSA Campaign Number: 24V797000 (Power Train). The contact had the vehicle towed to a dealer, who diagnosed the vehicle and determined that the transmission valve body had failed and needed to be replaced. The contact discussed the recall and was advised by the dealer that the VIN was not included in the recall. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 70,000.

The contact owns a 2025 GMC Yukon. The contact stated that while driving at an undisclosed speed, the vehicle unexpectedly went into LIMP Mode with a limited speed availability message displayed. The vehicle was restarted; however, the failure recurred. The vehicle was taken to the dealer, where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 8,837