2025 GMC SIERRA 2500

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 si

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 si

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 si

Burning an unusual amount of oil. Have seen several instances of blue smoke in the exhaust. Have had to add over a quart of oil twice in less than 6500 miles.

Had a minor wreck was to be two weeks to then it had to have a new frame they said it coun't be repair if a minor wreck can do this much damage there is a problem with subpar frames that any sudden stops or turns

Had a minor wreck was to be two weeks to then it had to have a new frame they said it coun't be repair if a minor wreck can do this much damage there is a problem with subpar frames that any sudden stops or turns

The contact owns a 2025 GMC Sierra 2500. The contact researched online and became aware that there was a recent recall under NHTSA Campaign Number: 25V815000 (Equipment) for the Owner's Manual. The contact stated that the vehicle was sold without the Owner's Manual. The contact stated that the manufacturer was called and was advised that the recall was only related to the 2026 Chevrolet Silverado models and the vehicle was not the same year, make or model. The contact was attempting to retain a physical copy of the Owner’s Manual and thought that it was a safety issue since there was a safety recall. The contact had not experienced a failure.

transmission locked up 8 times from 1,050 miles to current 3,885 miles. It has happens each time around 40 mph. Each time it’s like hitting the brakes. The 8th time it locked really hard like slamming on the brakes. I’m worried with winter months what will happen on snow/ice covered roads. Called dealership and was told GM refuses to do anything until it completely fails. It seems they know what the problem is but refuse to fix till the truck stops moving during complete failure. No warning lamps and dealer ship says they can’t replicate it.

i experience a steering wheel shimmy between the speeds of 70- 75 miles an hour

The accident occurred when the tailgate opened without warning or any buttons being pushed while towing a boat trailer. The tailgate become bound between the truck and trailer. The tailgate was damaged and limited my ability to turn the truck. My truck is normally parked in a garage and doesn’t sit in the weather. This truck is my 3rd vehicle so it doesn’t really get driven unless it is pulling a trailer, I tow with it all the time but very rarely use the bed or tailgate. Monday June 16 – Drove from Gallatin, Tn – Eddyville, Ky – Paducah, Ky the weather was constantly heavy rain and wind. Tuesday June 17 – Drove from Paducah, Ky to Defeated, TN more of the same bad storm. There were 3 of us and no one opened the tailgate, we hooked up to my boat and drove less than a quarter mile to the boat ramp, when we arrived, the tailgate had opened and the stairs on the boat had impacted the small part of the tailgate during a right turn. Prior to leaving the driveway and af

See attached document for complaint.

See attached document for complaint.

We were towing a fifth wheel camper with our truck on an interstate highway in Pennsylvania when our serpentine belt burst suddenly and without warning. Our truck is a 2025 model with only 10,000 miles driven. We lost all power steering and power brakes of both the truck and the camper and the motor shut off while we were driving at 65 mph. My husband struggled to gain control of the truck and camper which was severely fishtailing and was eventually able to get over to the shoulder and stop the vehicles. We were towed to a GMC dealership where a factory technician happened to be on site providing an in-service for the dealership's service team. He inspected our truck and we were told that he said that GMC is aware of catastrophic failures in these serpentine belts. We were also told that he took photos and was sending a report to the GMC factory regarding our situation. When the serpentine belt blew, it damaged fan blades, shroud, oxygen sensors and our air conditioner belt (wh

The contact owns a 2025 GMC Sierra 2500. The contact stated that while depressing the brake pedal to come to a complete stop, the brakes made a loud whistling and squealing sound. There were no warning lights illuminated. The vehicle was taken to the dealer, Bellamy Strickland Chevrolet GMC (145 Industrial Blvd, McDonough, GA 30253); who was unable to determine the cause of the failure. The dealer informed the contact that it was a known issue with no fix for the failure. The vehicle was not repaired. The vehicle was taken to a second dealer, who was also unable to diagnose the vehicle. The manufacturer was not informed of the failure. The mileage was approximately 5,000.

Mileage: 5,000

While towing a less than 2000 lb trailer I had total loss of power steering when speeds dropped below about 5 mph. I got off interstate and was turning right at the end of exit ramp and I could barely turn the vehicle. At the next stop sign it did the same thing. I stopped turned off the vehicle and restarted it and it continued this for the next few miles. Then just as suddenly as it started it stopped doing this and worked fine the rest of my trip.

We noticed that the brakes were really soft. We literally had to push on the brakes with excessive force. We took it to Lynch - West Bend, WI for a service call and was told that nothing was wrong with it. After leaving the dealership we did our own research (the hubby is a certified master technician himself). Come to find out through GM, contacts through TBM brakes and Duramax Forum.com "brake pedal effort" we found the issue and a solution and we fixed it ourselves. This truck is brand spanking new and the dealership threw their hands in the air with a safety issue and let us drive out of the parking lot. Imagine driving away after being told no issue to end up in an accident due to failed brakes. Who's to blame for that? Certainly not the customer. It was only when the new car sales manager took the truck for a drive, he agreed that there was a problem. - too late we took it home and fixed it ourselves. This problem needs to be looked into seeing its a known issue!

The passenger side rear wheel went into a pothole while making a right turn on a city street. This resulted in the right rear leaf spring breaking at the forward mounting point. This caused thr rear axle to swivel impacting the rear of the wheel well. The ESC malfunction indicator and impact sensor malfunction llights illuminated appropriately 2-3 miles later after I was in a highway. This is a significant safety concern as I was at an increased speed in heavy traffic by the time the lights illuminated. This not only puts the vehicle occupants at risk, this is potentially a significant risk to other motorist. There were no noticeable indications of damage besides pulling until I was at appropriately 55mph on the highway. The vehicle is currently at a dealership for repair.

The contact owns a 2025 GMC Sierra 2500. The contact stated that while driving at an undisclosed speed, after driving over a small pothole on the road, the alignment was dramatically altered, causing the vehicle to slightly veer out of the intended lane even though the steering wheel was centered. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The contact stated that he previously owned another vehicle of the same year, make, and model that had experienced the same failure and a case was filed with the manufacturer for the vehicle, resulting in a buyback. The failure mileage was 2,000.

Mileage: 2,000

Experienced loss of power steering, loss of brakes

Experienced loss of power steering, loss of brakes