2015 GMC SIERRA 1500 Complaints

I am reporting a critical issue with the transmission. The transmission frequently slips, hesitates, and jerks unexpectedly during acceleration and gear shifts. On multiple occasions, the vehicle has lost power or failed to respond while entering intersections, merging onto highways, or attempting to accelerate—posing a serious safety risk. The issue often occurs without warning and has worsened over time. Additionally, there are instances of harsh downshifting, delayed engagement from park to drive, and sudden lurching forward or backward, which could easily result in a collision. Despite visits to the dealership and complaints made, the issue has not been resolved, and I’ve learned that many other owners of this same model have reported nearly identical symptoms. This appears to be a systemic problem with the transmission system. Given the safety risk, especially in traffic and at high speeds, I strongly believe this defect warrants immediate investigation and a formal recall.

The contact owns a 2015 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. No warning lights were illuminated. The contact noticed an abnormal sound, and the vehicle rolled forward before the vehicle stopped. The vehicle was taken to the dealer but was not diagnosed. The dealer was made aware of the failure. The contact was informed of an unknown recall; however, the recall repair had expired. The contact had not received a recall notification. The vehicle was not diagnosed or repaired by an independent mechanic. The manufacturer was made aware of the failure and confirmed that the recall had expired in June 2024. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 75,000.

The contact owns a 2015 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. The vehicle was taken to the dealer; however, the vehicle was not diagnosed. The vehicle was not repaired. The contact stated that the failure became a persistent failure. The manufacturer was made aware of the failure. The contact referenced an unknown recall repair as a possible cause of the failure; however, the VIN was not included. The failure mileage was unknown.

With all the GM engine problems being recalled, the known issue witht he AFM/DOD on all the models 2013 and up on 5.3L and 6.2L engines should have been recalled. The valves are known to collapse and nending push rods, causing damage to the cam shaft. This can cause ht eengine not to run. The symptoms and possible icidents include the same as the current recall NHTSA Campaign Number: 25V274000. My engine has been repaired twice now due to this AFM/DOD issue. I have all the paperwork from GM dealer that repaired it. I will upload the first repair, I need to scan the second repair. The engine is now making the ticking valve sound ans the vehicle is services regularly. What component or system failed or malfunctioned, and is it available for inspection upon request? AFM/DOD valves collapse causing enegine damage. How was your safety or the safety of others put at risk? Lack of power while driving, loud engine knock Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, by the dealer Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Insepcted by the dealer, and only the damaged parts replaced, not all the valves that can still collapse. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No warning, engine light came on due to misfire on both incidents.

A valve spring broke while going around 40 mph. Was not accelerating when it happened. Destroyed the piston, head and cracked the block. Once apart found the AFM lifter had started to wipe a lobe on the cam. Engine shut off after running real rough luckily my son was able to pull over. Truck had regular service and taken good care of. My favorite truck I have ever had. Had 137,000 miles on the odometer. This could have ended badly.

The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle stalled with the check engine warning light illuminated. The vehicle was able to be restarted. The vehicle was taken to an independent mechanic, where it was diagnosed that the engine had failed and needed to be replaced. The vehicle was not repaired. The vehicle was taken to the dealer, where the diagnostic result was confirmed. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 97,000.

The contact owns a 2015 GMC Sierra 1500. The contact stated while driving approximately 50 MPH, the vehicle started to lose motive power and then stalled. The contact stated that there was a black cloud of smoke coming from the exhaust pipe. The check engine warning light was illuminated. The contact had the vehicle towed to an independent mechanic. The vehicle was diagnosed, and it was determined that the rod bearings had failed and needed to be replaced. The vehicle was not yet repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 122,000.

I've had problems with the brakes for several years, the pedal is very hard at low speed. I've seen a recall but not on my car???

"NHTSA campaign: 19V645000 AS the vacuum level drops, the brake assist decreases, increasing braking effort, extending the distance required to stop the vehicle, thereby increasing the risk of a crash." Our vehicle was serviced and repaired for this problem under the recall on 9/6/2019, however, it is now happening again. Is there a second recall for this problem, and/or what can be done to remedy the defective equipment?

The contact owns a 2015 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the transmission was difficult to shift into gear, with the check engine warning light illuminated. The vehicle was taken to an independent mechanic but was not diagnosed or repaired. The dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 144,000.