2025 GMC Sierra 2500 problems

“Power steering pump failed when decelerating after 9500 miles. When power steering pump fails, power assisted braking also fails. Upon deceleration, I could not turn the steering wheel at all or stop the vehicle without extreme pressure on the brake pedal. I narrowly avoided impact with a concrete barricade at the entrance to a parking lot. GM issued a technical bulletin (DCS7112) on January 16, 2025 identifying the problem and failure and directing dealerships to replace the pump on inventory vehicles. No mention was made to repair or notify owners of the potential problem.”

“My 2025 Sierra 2500HD repeatedly displays “Trailer Brakes Disabled—Service Required” with a lithium- and solar-equipped trailer. The truck passes the EL-52641 simulator, but the failure occurs intermittently while towing and resets after Park or reconnecting the trailer. This closely matches the higher-trailer-battery-voltage/backfeed condition described in N232414840. Please open a TAC case and determine whether my 2025 has the revised Trailer Brake Power Module or whether GM engineering authorizes module replacement.”

“Component / System Failure The exhaust system, specifically the exhaust manifolds and previously the EGR system components, appear to have failed or malfunctioned, allowing exhaust gases to enter the passenger cabin. The dealer initially replaced the EGR cooler diverter on December 23, 2025. However, the condition persisted. On February 3, 2026, cracked exhaust manifolds were identified by the dealership, and a major front-end teardown was advised to complete the repair. The vehicle is currently available for inspection upon request. ⸻ How Safety Was Put at Risk The malfunction allowed exhaust gases, including carbon monoxide, to enter the passenger cabin during vehicle operation. Carbon monoxide readings inside the cabin reached up to 50 parts per million (ppm) while driving. Carbon monoxide is a toxic gas that can cause: •Headaches •Dizziness •Impaired concentration •Nausea •Vision disturbances Because carbon monoxide is odorless and colorless, this presents a significant safety risk, particularly at highway speeds where driver alertness is critical. The exposure occurred while operating the vehicle in normal driving conditions. This created a potential risk…”

“The transfer case leaked out all the fluid while driving over a period of time and damaged internal parts before the first oil change. This has happened 2 times now, and is currently leaking again with less than 10k miles.”

“A driver hit me in the side of the car at around 70 mph to where it bent the frame of the truck and the airbags did not deploy causing a major issue and my daughters head to hit the side window.no warning lamps and it’s currently at a body shop right now”

“My 2025 GMC Sierra 2500 experienced repeated electrical failures that caused complete battery drainage and multiple overnight no‑start conditions within the first year of ownership. These failures occurred in extreme desert heat, where temperatures in [XXX] reach 120°F. A vehicle that repeatedly fails to start in these conditions creates a serious safety hazard, including risk of heat‑related medical emergencies if stranded. The defect persisted despite multiple repair attempts and two battery replacements. The dealership ultimately told me I would “need to replace batteries as needed,” instead of diagnosing the underlying electrical issue. Detailed Description of the Problem Multiple overnight no‑start incidents Several jump‑start events required XXX – 15,265 miles: Battery replaced due to electrical drainage XXX: Battery replaced again for the same defect Electrical system continued to fail after repairs Dealer advised ongoing battery replacement rather than addressing root cause The truck was unreliable and unsafe in extreme heat. A no‑start condition in 120°F temperatures can leave occupants stranded without air conditioning, posing a life‑threatening risk.…”