2025 GMC Sierra 1500

I was driving and the engine abruptly stalled. The truck self-shifted to Neutral. Once stopped, I shifted to Park to attempt a restart. It would not crank. I was on a 2-lane road so I did not have a shoulder. Once I realized it would not restart I tried to shift to Neutral so I could push it to a subdivision road about 50 yards away only to find out my transmission has no ability to shift to Neutral (the dealer confirmed this later). So I was stuck on the road for hours just over the crest of a hill with people coming up on me and my family at 50mph. It was a windy 10 degrees so we could not wait on the side of the road where we would have been safer. This is how people get killed; being stopped where people can't see you and do not expect you to be stopped. Why can I not get the truck off the road? If this happened on an 8-lane highway how would I get to a shoulder, even after traffic had stopped behind me? On top of all that, the problem with the truck ended up being an engine bearing failure (per the dealership service dept) that is a known problem with this engine and truck build date. General Motors needs to proactively diagnose and get these engines replaced before someone gets hurt. There is a TSB issued for the bearing issue but when I asked my dealer about it a month ago, before the failure, they acted like they knew nothing about it and told me to bring it in if I hear noises. If they had offered to check the crankshaft endplay when I asked about it ( as the TSB suggests), I may not have gotten stranded and my family's safety put at risk. There were no warning lamps, and no strange noises before the engine seized. My fuel economy had decreased by about 20% in the last month but that may be from cold weather operating conditions. I have a separate electrical issue that I've been chasing down and I assumed this stall condition was related to that. But the dealer confirmed this was a bearing failure.

I bought my truck new in June 2025. On the night of December 29, 2025, with around 9,300 miles on the odometer, I began to hear a knocking sound coming from the engine while I was driving it back to my house from my mother's house. The sound got progressively louder and louder. The truck eventually displayed a "reduced acceleration drive with care" warning. I thought catastrophic engine failure was imminent and did not believe I could make it home. I called my in-laws (they were closer to my location than my house), agreed to park it there overnight, and thankfully made it to their house. The next day the truck was towed to the GMC dealership. A week later, GMC diagnosed this issue as a thrust bearing/crankshaft issue and agreed to replace the entire engine. A crankshaft issue in a new diesel engine should not occur, yet it did. My vehicle is currently being repaired, so the dealership said they had no repair records to provide me. This is the link to the video of the sound it was making after I made it to the in-laws: [XXX] I had just dropped off my [XXX] child with my mother about twenty minutes earlier. I was extremely close to being stranded on the side of the highway at night in the December cold with a [XXX] baby. Thankfully, that did not happen, but it was a close call. My cousin also has had a similar issue with the exact same make and model of his truck. I believe this engine is not being manufactured according to the design specifications and it is a danger to the public until the manufacturing issue with the supplier is adequately corrected. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2025 GMC Sierra 1500. The contact stated that while driving 75 MPH with the cruise control activated, the vehicle failed to accelerate as intended while depressing the accelerator pedal, and the vehicle decelerated to 10 MPH. In addition, the vehicle came to an abrupt stop independently. The contact’s upper body almost struck the front windshield. There was no warning light illuminated. The contact stated that shortly afterwards, the vehicle resumed driving normally at 75 MPH; however, the failure reoccurred after a short distance. The vehicle failed to accelerate as intended while depressing the accelerator pedal and abruptly came to a stop. The vehicle then resumed driving normally. No warning lights were illuminated. The contact arrived at the residence, and the vehicle was towed to the dealer. The vehicle remained at the dealer awaiting a diagnostic test. The manufacturer was not made aware of the failure. The approximate failure mileage was 7,800.

The vehicle has a vibration and stuttering feel during highway driving. Cruise between 70-75 has off and on again vibration is seat, steering wheel, and center console. The issue feels more pronounced between 60-65 and exhibits more of a hum, much like a washing machine drum that is out of balance. I have had the truck at 2 different dealerships and they have insisted it was a whee balance issue. I have also had the truck balanced at Costco. None of these issues have been alleviated with wheel balance. The dealership, where the truck was purchased, refused to test the truck at highway speeds and would only drive it for a short period at speeds up to 55mph. I have also reached out to GMC customer service, and they simply regurgitated what the dealer indicated about balance and testing at 55 mph or less in town. There seems to be a number of TSBs out on this issue. Most related to torque converter issues, but none of the dealers have indicated that my truck is impacted by any of the current TSBs, even though it exhibits all the symptoms. Not sure of the safety replications, but I am disappointed in the fact that the truck has had this issue since around 1,000 miles, and it seems like the dealer service departments are just ignoring it and refusing to do a thorough evaluation of the issue unless a code triggers or until a major failure occurs

I am writing to express my extreme disappointment and serious concern regarding a critical safety failure I experienced with my 2025 GMC Sierra 1500 Denali Unlimited (VIN: [XXX] ), which I purchased brand new in April 2025 from Cavender GMC, San Antonio, TX. On Friday, [XXX], with fewer than 9,000 miles on the vehicle, I was driving on the highway at about 65 MPH, with my minor son in the vehicle when the dash suddenly displayed a Traction Control (TRC) Fault message, followed immediately by "Acceleration is Limited." The truck experienced a severe and unexpected power loss, severely restricting my ability to accelerate or maintain safe highway speeds. I was forced to pull off the road abruptly to avoid a potentially dangerous situation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

This is the second time in 2 days!! While driving ~35MPH the truck experienced a harsh transmission shift followed by a sudden loss of acceleration and entered shutdown mode to protect the engine. The steering became stiff, all dashboard warning lights illuminated, and a message appeared on the driver display indicating a transmission issue and advising to drive with caution. This created an extremely hazardous condition for me while driving on s busy stretch of road. I pulled onto the side of the road, came to a complete stop, shifted into park, and turned off the engine. Upon restarting the vehicle, the Check Engine Light remained on, and the transmission continued to shift abnormally at low speeds, including some noticeable shuddering. My GMC application recorded the issue and reminded me to schedule service.

While driving on the highway at 70 MPH, the truck experienced a harsh transmission shift followed by a sudden loss of acceleration and entered shutdown mode to protect the engine. The steering became stiff, all dashboard warning lights illuminated, and a message appeared on the driver display indicating a transmission issue and advising to drive with caution. The RPMs surged and the truck struggled to maintain a speed of 45 MPH while the remaining at 4000 RPM. This created an extremely hazardous situation for both me and my passenger. I safely pulled into the breakdown lane, came to a complete stop, shifted into park, and turned off the engine. Upon restarting the vehicle, the Check Engine Light remained on, and the transmission continued to shift abnormally at low speeds, including noticeable shuddering.