My vehicle inadvertently locks the rear tires at highway speeds and then releases and drives. In some instances it may brake several times causing the tires to burn rubber for a short distance causing rear traffic to either swerve to avoid rear ending me and in a couple instances causes the rear following traffic to abruptly change lanes to avoid rear ending

- Southfield, MI, USA

Service Trailer Brake System Alert constantly going off

- Mandeville, LA, USA

Truck has had multiple issues related to the electrical system and truck modules. It is my opinion that these are all related to voltage issues or module problems. i have had multiple infotainment issues with delays loading, freezing up etc. dealer has ran updates and checks with nothing found. In October around $35k miles the truck Radio would not work if i used the push button start. if i shut the truck off opened the door and let everything reset i could push the start button in the truck and the radio would work majority of the time. The next day i went out to a completely dead truck. I talked to my service department at the local dealer and they said i would need to bring it in but suggested i disconnect the batteries and recharge the batteries. after doing so everything started working correctly. it fixed my radio problem and never went dead again. since then i have experienced popping noises through the speakers when playing music occasionally. over the last few weeks i noticed the engine does not attempt to increase cold idle speed until i press the brake to put it in gear. January 22nd i hit the autostart button and it did not work. i started the truck and it had CEL, Traction control, park brake and wrench, lights on with service emissions, and power reduced messages displayed. Truck is running odd. codes present are (ENGINE GMLAN)P0118 - engine coolant temp circuit high voltage, (BRAKES GMLAN_ABS) U0401- invalid data from engine control module, P0562- system voltage low, (HVAC CONTROLS GMLAN_HVAC) B1325 -. control module power circuit. Truck is starting and charging fine. No connection issues at batteries. There are many TSB's and many complaints regarding similar issues. common brake and emissions faults with minor differences. Module failures, communication faults, and or electrical faults are likely causing all of these similar issues. they need to be categorized as the same failure group which will show GM has a bigger issue.

- Shawnee, KS, USA

While driving my 2020 GMC 2500 Denali with the Duramax Diesel engine, the power assist for the steering and brakes failed without any warning. This made the truck nearly impossible to steer and stop. Luckily, I was able to avoid a collision and get the truck stopped in a safe location. The truck is currently being towed to Rivard GMC in Tampa, Fl. Doing an internet search, I found this problem has happened to others as well. Please ask GM to rectify this extremely dangerous defect.

- Apollo Beach, FL, USA

Brakes since new squeeled. Took to dealer and dealer said it was normal. Have had the truck about 11 months now. Dealer stated GM now uses a different pad material and I would have to pay for it at a cost of close to $1,000 to replace the pads.

- Norwalk, CA, USA

My brakes are squeaking very loudly they have been since August. I was driving down the road on US1 and prepared to stop to make a turn and my truck would not stop. I was making a right turn and ended up in the other lane of oncoming traffic sideways because I tried to turn my truck to slow it down. I complained about my brakes several times to the dealership they ordered me new brakes without even looking at my vehicle around August 8th. We are now at the last two days of September and they still do not know when the brakes will come in. This is a serious safety issue at this point. I have no other vehicle to drive. I bought a 70,000 truck and my and my family's safety is on the line. GMC needs to find me a comparable loaner vehicle until my truck is repaired.

- Titusville, FL, USA

The contact owns a 2020 GMC Sierra 2500. The contact stated that while driving and towing a trailer, she discovered that the brakes were overheating. There was a strong burning hot odor coming from the brakes. The contact pulled over and discovered all four brake rotors were extremely hot. The contact drove and dropped off the trailer. The contact drove 20 mph and down shifted to control the speed to get back home. The dealer dave arbogast Buick-GMC (3540 S co road 25A, troy, oh 45373, (937) 335-0068) stated that incorrect brake pads were installed on the vehicle from the factory and there was a technical service bulletin for the failure. The vehicle was not repaired due to the replacement parts not being available. The manufacturer was contacted and promised to provide a callback. The failure mileage was 500.

- Ludlow Falls, OH, USA

The contact owns a 2020 GMC Sierra 2500. While driving 5 mph, the brakes engaged automatically and the traction control warning indicator illuminated. The vehicle was taken several times to carl black Chevrolet Buick GMC (located at 1110 roberts boulevard northwest, kennesaw, ga 30144, (888) 457-2417). The dealer diagnosed that the speed sensor needed to be replaced. The vehicle was repaired, but the failure continued. The dealer diagnosed the vehicle again and stated that the wheel hubs needed to be replaced. The vehicle was repaired, but the failure recurred. The dealer diagnosed the vehicle a third time and stated that an unknown steering angle sensor needed to be updated. The vehicle was repaired, but the failure continued. The manufacturer was informed of the failure. The failure mileage was 571.

- Grovetown, GA, USA