2025 GMC Sierra 1500

The engine shuts off while slowing down. It cuts off cleanly and the entire dash lights up and the transmission shifts to neutral. The driver display says to put the truck in park and hit the start button. After you do this the truck runs fine for about 2k-3k miles and does it again. I has done this 5 times within 10k miles. The dealer says nothing is wrong with the truck because the computer doesn't record any codes. This happens regardless of whether the auto stop/start feature is on or off.

Engine started making a loud knocking noise and it sounded like the engine was about to throw a rod. Turned engine off and called GM. Vehicle was towed to dealership and it was diagnosed with a thrust bearing failure. My truck only had 14k miles on it. To fix the bearing issue, it will need a new engine. GM does not currently have engines to replace the faulty ones so it has sat at the dealership for 3 weeks with No ETA as to when it will be fixed. This is apparently a common problem in the 2025-2026 models LZ0 3 liter diesel. They are still selling these affected vehicles currently, knowing that they may have a problem. GM needs to issue a recall and take these vehicles back.

Going down the highway at highway speeds engine fully seized up almost cause an accident,, totally locked up engine, got towed to dealer and they said total engine failure just like in the priare years., been waiting for a new engine for almost 3month due to these failing on other cars,, they will be replacing my old engine with same engine that in prone to locking up. only a matter of time till the new one does the same thing. i want a buy back but they say it has 70k miles and its over the warranty and they wont buy back

Interior Electrical System / Center Console Wireless Charging Pad The plastic housing surrounding the factory wireless phone charging pad in the center console has visibly melted and deformed. The damage is localized to the area directly above/around the induction charging coil, with no similar heat damage to adjacent console plastics, indicating the wireless charging module itself is the heat source. I stopped using this charging location upon noticing the deformation. This appears to be a component overheating defect that poses a potential fire risk if left in continued use. I am not aware of an existing recall or technical service bulletin covering physical melting of this component (existing GM bulletins address intermittent charging function only, not heat damage to plastic). Requesting this be documented and investigated.

What component or system failed or malfunctioned, and is it available for inspection upon request? The engine/powertrain failed. The vehicle is a 2025 GMC Sierra 1500 equipped with the 6.2L V8 engine. The engine developed a severe knocking noise and loss of power at approximately 5,545 miles. The vehicle was taken to the GM dealership, where an engine replacement was approved. The failed engine/component may be available for inspection through the dealership or GM, depending on whether it has already been removed or returned to the manufacturer. How was your safety or the safety of others put at risk? The engine failure created a safety concern because the vehicle experienced reduced power/loss of propulsion while being operated. This could have put me and other drivers at risk because a sudden loss of engine power can make it difficult to safely maintain speed, merge, tow, or move the vehicle out of traffic. The issue occurred at very low mileage and without enough warning to prevent the failure. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The problem was confirmed by a GM dealership. The dealer diagnosed the engine failure and GM approved an engine replacement under warranty. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? The vehicle was inspected by the GM dealership. GM was involved in approving the engine replacement under warranty. To my knowledge, the vehicle has not been inspected by police or insurance representatives. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Prior to the failure, the vehicle developed a severe engine knocking noise and reduced power/lack of power. These symptoms appeared shortly before the engine failure at approximately 5,545 miles. I do not recall any specific warning lamps or messages before the failure, unless the dealership records

The adaptive cruise control has twice unexpectedly applied the brakes with sufficient force to result in a minor whiplash situation of a sore neck. Both times were driving on a two-lane highway traveling between 65-70 mph (cruise control was set a 68 mph) with no vehicles in the lane in front of me. The adaptive cruise control appeared to interpret oncoming traffic as a vehicle in front of me and aggressively applied the brakes, rapidly dropping my speed from 68 mph to the 35 mph range. Brakes were applied with such force that my neck was sore for about two weeks after each incident. My vehicle also has automatic emergency braking (AEB), but I don't believe this system was activated as the warning lamp on the dash and the audible alert was not activated in either situation. These incidents are related to the adaptive cruise control feature, not the AEB system. The dealership has not had an opportunity to inspect the vehicle yet, or any other agencies. In both incidents, no warning lamps or audible alerts were activated.

While driving at highway speed, my 2025 GMC Sierra suddenly began slowing down without warning and lost propulsion. When I pressed the accelerator, there was no acceleration response. The vehicle felt like it was braking or dragging instead of accelerating, creating a serious crash risk in traffic. A warning message appeared instructing me to “Put in neutral and restart truck.” I followed the instruction, but the vehicle would not restart. It sounded like it was attempting to start, but it would not start normally. A “Service ESC” warning also appeared. The vehicle was towed by AAA to a GMC dealership and remains available for inspection. The dealership provided a diagnostic trouble code report showing active codes: C2A07 Engine Control Module Indicated Torque Signal Malfunction; U0101 Lost Communication with Transmission Control Module; U0131 Lost Communication with Power Steering Control Module; U0140 Lost Communication with Body Control Module; U0146 Lost Communication with Central Gateway Module; U160F Lost Communication with Brake System Control Module 1 on CAN Bus 1; U1611 Lost Communication with Engine Control Module on CAN Bus 2; and U3003 Battery Voltage Circuit Voltage Below Threshold. The vehicle had approximately 22,000 miles at the time of the incident. The failure has not been repaired at the time of this complaint. The concern appears to involve a safety-related electrical, propulsion, powertrain, ESC/brake, and module communication failure that caused sudden loss of propulsion, no acceleration response, warning messages, and a no-start condition.