2026 GMC Sierra 2500 Problems

The contact owns a 2026 GMC Sierra 2500. The contact stated that the audio system was inoperable, and the alarms, chimes, and rear cross-traffic alert chimes were inaudible. The contact stated that disconnecting and reconnecting the battery restored the audio system operation intermittently. The vehicle was taken to the dealer, where the radio control module, the amplifier and a software were replaced; however, the failure persisted. The dealer informed the contact that the failure was a software issue; however, the fix was unavailable, and the manufacturer stated that the vehicle was drivable. The manufacturer was notified of the failure by phone. The failure mileage was approximately 1,600.

My 2026 GMC Sierra AT4 HD intermittently has no power steering assistance when I start the vehicle, making it extremely difficult to steer. This occurs randomly, approximately once every one to two weeks, and has nearly caused me to hit another vehicle on multiple occasions. A few months ago, the dealership inspected the truck, performed a software update, and told me the issue should be resolved. However, the same problem occurred again after that service visit. I contacted the dealership and requested another service appointment and a loaner vehicle because I need transportation to work. I was told there is a waiting list for loaners. GMC customer service has opened a case and is contacting the dealership to help arrange service sooner. The steering issue remains unresolved, and I am concerned it could cause a collision.

My 2026 GMC Sierra AT4 HD intermittently has no power steering assistance when I start the vehicle, making it extremely difficult to steer. This occurs randomly, approximately once every one to two weeks, and has nearly caused me to hit another vehicle on multiple occasions. A few months ago, the dealership inspected the truck, performed a software update, and told me the issue should be resolved. However, the same problem occurred again after that service visit. I contacted the dealership and requested another service appointment and a loaner vehicle because I need transportation to work. I was told there is a waiting list for loaners. GMC customer service has opened a case and is contacting the dealership to help arrange service sooner. The steering issue remains unresolved, and I am concerned it could cause a collision.

Ongoing issues with Steering pull to right, and brake pull to hard right when applying brakes, which also turns steering wheel to right upon application. Have to keep steering wheel towards left with constant pressure to go in straight line and when braking. Driver has to be aware of changing road conditions that could affect that. Multiple inspections at multiple dealers have found no obvious issues, and multiple alignments performed, with tires also being replaced have had no success in correcting issue. Front suspension starting to feel loose due, and rear suspension squeak when going over bumps. Also recently found rear axle is shifted slightly to right. Suspect all are related. No parts replaced to date other than the tires. Happens daily. No accidents to date. Daily driver with long trips at times. Steering pull Issue has present since new but everything else has occurred since about 1800 miles and has progressively become worse. Conditions becomes worse at highway/freeway speeds of 65 to 80, but occurs as low as 10mph. Going back to 3rd dealer to look at it again. Truck is 2026 with 10,583 miles.

No Incident Occurred. Tire Size 275/65R20. Tire Pressure Fluctuating between 59 and 71 PSI. 3 of 4 tires appear to have a defect. Was detailing the vehicle on 7/26/26 and noticed a tear in the Side wall on the Passenger side rear tire. About 3/4" to 1 inch away from the rim along the sidewall. Running parallel with the rim for about 4". Found similar defects and indentation lines on the Passenger side front and Drivers side rear, in varying lengths around the rim. Vehicle has Not Towed, had a Load in the bed or used off road. 1,897 miles all Pavement Mixed HWY and Street use. Vehicle was Purchased 6/25/26. Scheduled for Service 7/28/26. Will have the Dealer look at the tires.

DOT AH9K82 3425 LT265/70R17 121/118Q All four brand new tires on my brand new truck have bulges on the sides of the tires. The truck feels floaty and unsafe at highway speeds. The car dealership is saying it’s fine, won’t replace them, and says it’s a known issue with the tire.

Ongoing issues with Steering pull to right, and brake pull to hard right when applying brakes, which also turns steering wheel to right upon application. Have to keep steering wheel towards left with constant pressure to go in straight line and when braking. Driver has to be aware of changing road conditions that could affect that. Multiple inspections at multiple dealers have found no obvious issues, and multiple alignments performed, with tires also being replaced have had no success in correcting issue. Front suspension starting to feel loose due, and rear suspension squeak when going over bumps. Also recently found rear axle is shifted slightly to right. Suspect all are related. No parts replaced to date other than the tires. Happens daily. No accidents to date. Daily driver with long trips at times. Steering pull Issue has present since new but everything else has occurred since about 1800 miles and has progressively become worse. Conditions becomes worse at highway/freeway speeds of 65 to 80, but occurs as low as 10mph. Going back to 3rd dealer to look at it again. Truck is 2026 with 10,583 miles.

Brand new delivery there was a noise that changes with engine RPM. It also changed with turning the steering wheel. The dealer diagnosed a bad power steering pump. Due to possible metallic contamination all related parts that are connected to the power steering pump including the HydroBoost brake assist are going to be replaced

Metal/chrome decal on seat pulls hair frequently, making sitting back in a safe position uncomfortable. Fix this issue.

Aug 14th, 9:49 pm - Vehicle was placed in park and driver got out. A few seconds later the vehicle started moving forward under its own power towards the driver who was now infront of vehicle walking foward away from vehicle. Passenger hopped over the driver seat to press on brake pedal to stop vehicle. At same time, driver turned around and noticed vehicle moving towards him. Passenger was able to stop vehicle but not before it ran off the driveway and into and over a recreational firepit area. Driver was on opposite side of this. Driver got in to vehicle, verified transmission was now fully engaged in Park, and reversed the vehicle off firepit area. Damage to both vehicle, and firepit ring and landscaping area. Security footage later confirmed vehicle was placed in park, brake lights went out, and vehicle remained stationary for approximately 3 to 5 seconds before driver exited vehicle. It was when driver shut door that vehicle then moved, as if the Parking pin did not engage or failed to stay engaged. Owner traded vehicle in with another dealer soon after, due to other ongoing issues involving the steering and brake system that had not been resolved. Approximately 11,580 miles on vehicle at the time of incident. No personal injuries reported.

Ongoing issues with Steering pull to right, and brake pull to hard right when applying brakes, which also turns steering wheel to right upon application. Have to keep steering wheel towards left with constant pressure to go in straight line and when braking. Driver has to be aware of changing road conditions that could affect that. Multiple inspections at multiple dealers have found no obvious issues, and multiple alignments performed, with tires also being replaced have had no success in correcting issue. Front suspension starting to feel loose due, and rear suspension squeak when going over bumps. Also recently found rear axle is shifted slightly to right. Suspect all are related. No parts replaced to date other than the tires. Happens daily. No accidents to date. Daily driver with long trips at times. Steering pull Issue has present since new but everything else has occurred since about 1800 miles and has progressively become worse. Conditions becomes worse at highway/freeway speeds of 65 to 80, but occurs as low as 10mph. Going back to 3rd dealer to look at it again. Truck is 2026 with 10,583 miles.

Driver’s side sun visor does not maintain its position. If placed in the half-way position for instance, it completely drops all the way down after a few minutes of driving creating a viewing hazard. Visor needs to constantly be repositioned which takes a hand off the wheel each time creating a safety hazard.

I am filing a formal safety complaint regarding my 2026 GMC Sierra 2500HD Duramax (VIN [XXX]; 32,607 miles). While driving at highway speeds with Adaptive Cruise Control engaged, the truck intermittently applies the brakes suddenly and forcefully with no vehicle, pedestrian, or obstruction apparent in the roadway. On some occasions it decelerates from my set cruising speed to nearly a complete stop without my braking input or warning. This creates an immediate risk of a rear-end collision, particularly in highway traffic. These events have occurred repeatedly. The brake rotors now exhibit warping or vibration, which I suspect may be related to the repeated severe braking; the cause has not been established. My previous 2025 GMC Sierra 2500HD Duramax experienced similar unexplained braking. I reported concerns but did not receive a satisfactory investigation and traded it at approximately 35,000 miles, believing the issue was isolated. The 2026 truck's behavior is worse. I purchased another GM truck without these features to maintain dependable transportation because I do not consider using Adaptive Cruise Control on this vehicle safe. I have located seven distinct online owner reports of similar unexpected braking in recent GMC Sierra and related Chevrolet Silverado trucks, including reported NHTSA complaint XXX; these reports have not been independently verified as the same defect. I request that NHTSA investigate potential false detection or unintended braking commands involving Adaptive Cruise Control and related systems on 2024–2026 GM trucks, obtain GM engineering and warranty records, and evaluate the risk to drivers and following traffic. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I recently purchased my vehicle from Big Star Dealership in Baytown Tx. At a little over 1000 miles i was towing a camper. The vehicle stalled, fuel pouring from engine. It was towed and repaired due to fuel pump failure. At a little over 3000 miles the vehicle would not start. Dealership initially said water contamination then changed it and said gasoline contamination and now they say DEF contamination. The vehicle stalling the first time almost caused me to wreck the vehicle

I recently purchased my vehicle from Big Star Dealership in Baytown Tx. At a little over 1000 miles i was towing a camper. The vehicle stalled, fuel pouring from engine. It was towed and repaired due to fuel pump failure. At a little over 3000 miles the vehicle would not start. Dealership initially said water contamination then changed it and said gasoline contamination and now they say DEF contamination. The vehicle stalling the first time almost caused me to wreck the vehicle