2025 GMC Sierra 2500

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. Frequency of the Problem The electrical failure occurred multiple times over several months, including late 2025, early 2026, and again in mid‑2026. The defect was consistent and repeatable. Consequences Risk of being stranded in extreme heat Loss of air conditioning during no‑start events Potential for heat exhaustion or heat stroke Vehicle unreliable for daily use Safety hazard for driver and passengers INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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 of driver impairment and increased risk of collision. ⸻ Has the Problem Been Reproduced or Confirmed? Yes. The vehicle was presented to the dealership three times for the same exhaust intrusion concern: •December 16, 2025 •December 29, 2025 •February 3, 2026 During the February 3 visit, the dealership confirmed cracked exhaust manifolds requiring major disassembly for repair. The carbon monoxide readings were observed during vehicle operation. The exhaust odor and intrusion symptoms were consistently present following the first attempted repair. ⸻ Has the Vehicle Been Inspected by Manufacturer or Others? The vehicle has been inspected by the authorized dealership on multiple occasions. Two manufacturer customer care cases were opened.