GMC Sierra 1500 won't start problems

Filed Nov 2, 2026 · Engine · CO

Information related to GMC 25V274 recall for 2023 GMC Sierra 1500 6.2L. Recall oil change inspection and change of oil to higher viscosity performed summer of 2025 (prior to my ownership). On May 17, 2026 the Truck lost engine power without warning and would not start again. Fortunately I was on a road and location where I could coast into a parking lot, but again the vehicle provided no advanced warning of any issue. Towed truck to dealership and determined that exact engine problem noted in recall had indeed occurred to engine. So GMC recall efforts to inspect and change oil had NO effect on the engine defect. Engine was replaced.

Filed Oct 29, 2026 · Fuel system · WA

On [XXX], at around [XXX] my 2023 GMC Sierra 1500 Elevation suddenly lost power while I was driving eastbound on [XXX]. The battery was still running, but the engine lost power and the accelerator did not respond and the truck would not move. I was stranded in the roadway. OnStar emailed me about a critical vehicle issue and reported DTC P129F. Because the truck was stopped in a live lane of traffic, I called 911. Responders blocked part of the road to protect me and to give the tow truck room to recover the vehicle. No one was injured, but this could easily have caused a serious collision. A few days later, I had the truck towed to Seaview GMC in Lynnwood, WA. The dealer diagnosed an internal failure of the fuel pump power control module, the K111 Fuel Pump Driver Control Module mentioned in the GM Bulletin earlier this year. This matches a known issue described in GM Service Bulletin 24-NA-139, which covers DTCs P129F and P023F and lists 2023 Sierra 1500 models. The bulletin describes symptoms including no-start and stalling. The dealership has attempted to charge me $200 for diagnosis and $261 for the fuel pump module. I had asked them if this was covered under warranty, they responded that they would check with their warranty specialist. This conversation happened at the Seaview GMC Dealer approximately 5pm on [XXX]. The informed me they would call the next day to confirm if this is covered or not covered by warranty. I am reporting this because a sudden loss of power while driving on a highway is a serious safety risk. I am concerned that other owners may experience the same failure at highway speed, and I would like the federal safety agency to review this issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 12, 2026 · Engine · OH

While towing a trailer on 6/26/26, the 6.2L L87 engine suffered a sudden drop in oil pressure, began knocking, and completely lost motive power on the roadway. Because the engine seized instantly, the vehicle experienced a sudden loss of power steering and power braking while managing the extreme weight of a trailer. This combination created a severe and immediate safety hazard, forcing me to maneuver a heavy, unpowered truck and trailer combination through active traffic to the shoulder without full steering or brake control, putting my life, my passengers' lives, and the safety of surrounding motorists at extreme risk. My dad read the codes before we took it to my mechanics and the only code I can remember is P0016. I took it and dropped it off at my local mechanics on 6/28/26. This is what my mechanic said: No Start-Truck came in not running. Had timing codes. I believe the crank bearing failed causing the engine to lose oil pressure. With the sudden loss of oil pressure, the timing chain tensioner slacked and caused the cam/crank to go out of time. Drained engine oil and found bearing material. We also cut oil filter open and found more bearing material. The timing cover was removed and verified the cam timing was off. In conclusion the engine has failed and will need full replacement. This is the exact failure mechanism under active the federal safety agency Investigation EA26005.

Filed Sep 21, 2026 · Engine · CO

I was backing out of my garage and truck made strange noise and shut off . Tried to restart but just made ding and wouldn't turn over . Dash lights went blank. Had vehicle towed to shop and mechanic stated it was crank and connecting rods after he dropped the oil pan. I ordered new OEM engine and waiting on delivery . Been 5 weeks now since order . Vehicle only has 106,000 miles on it and have had it since 20,000 miles and all maintenance has always been done . Engine can be inspected at shop as new engine has not arrived

Filed Sep 17, 2026 · Engine · GA

On 9-5-26 while on interstate 75 going about 75 miles per hour truck started losing propulsion and speed started dropping. No warning light or anything. Navigated over to shoulder turn truck off for about 5-10 minutes and started back. On 9-8-26 on the way from Dr. appt. starting truck up it acted like it didn't want to start but did. Eventually stopped at red light and truck died and wouldn't start. Dash board lighting up and when trying to start the engine would not turn over. No warning light or anything. Truck towed but had to drag on the wrecker due to wheels locked up. On 9-16 GMC advised engine fail and will need replacing at 12,000 miles. VERY UNACCEPTABLE FOR 2024. Truck was bought new in October 2023 with 4 miles. Found out it is a known issue with the 6.2 V8. Be careful. We could have been killed in the flow of traffic and truck losing power with no warning. Couldn't even turn hazard lights on or anything. 18 wheelers coming all around and we trying to navigate to safe spot on the shoulder when we was on the interstate. GMC need to get their stuff together, you are putting people lives is danger. GMC is feeling our anger right now. Who wants a new engine in a $90,000 top of the line truck

Filed Sep 10, 2026 · TX

The engine coolant control valve on my 2021 GMC Sierra 3.0L Duramax diesel failed. This specific component failure triggers an active vehicle 'No-Restart' safety event during automatic engine stop/start operations (per GM Service Bulletin #24-NA-070). This condition can suddenly prevent the vehicle from restarting when stopped at intersections or in active traffic, creating an immediate highway safety hazard and leaving the vehicle stranded. Additionally, the vehicle's radiator cooling fans run continuously at 100% maximum capacity as a system fail-safe, creating severe electrical drain. General Motors has issued a Special Coverage Adjustment (#N252508341) acknowledging the high failure rate of this part, but it is capped at 150,000 miles. Because this defect causes unexpected stalling/no-start safety risks in live traffic past this arbitrary mileage limit, a formal safety recall is required.

Filed Sep 9, 2026 · Engine · IL

Engine I believe The truck died while I was doing 78 MPH on the highway Dashboard stated “shift into neutral and press start” I pulled to the side of the road and did what it stated and it would not crank over. I also put it in park turned the vehicle off and back on to try to start it. The lights on the dashboard, all gauges, the AC, and everything works the truck just will not crank over. Check engine light came on but is not throwing any codes

Filed Sep 9, 2026 · Body, Electrical · GA

A GM warranty engine replacement was performed at Heyward Allen GMC in [XXX] on XXX at 70,415 miles. We purchase the vehicle on XXX with 73,904 miles and after driving for a month started having multiple malfunction indicator lights displaying, and experienced a no start condition. We took the vehicle to the Don Ledford GMC dealer in [XXX], and they performed a high level inspection. They found missing mounting brackets, loose wiring harness wires, broken and missing bolts. Issues all related to an engine replacement procedure. Deeming the vehicle unsafe to operate. The origin dealer that was paid through GMC to replace the engine is now refusing any responsibility for resolving these issues. Technicians have video evidence of the workmanship issues, documenting the sub- par repair work performed during the engine change. The vehicle now sits at the Don Ledford GMC dealer awaiting an estimated $4400 repair, before the vehicle is safe to operate on the road. The vehicle has been at the Don ledford dealer since XXX, and is still there today, XXX. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 9, 2026 · Electrical, Engine · NV

When updating the vehicle as prompted by the entrainment system the next day when attempting to start the vehicle it did not start. Vehicle had to be jumped then 6 warning lights came on and disappeared shortly after driving.

Filed Sep 3, 2026 · Engine · UT

2020 GMC Sierra 1500 AT4, 3.0L LM2 Duramax. In service 08/13/2020. Five glow plug failures on five different cylinders in under 19,000 miles, all at one GM dealer, all part 24000504: Cyl 1, 10/21/2024, 38,650 mi, P0671, RO 13714, warranty. Cyl 6, 11/05/2024, 38,793 mi, P1330, RO 26665, warranty. Cyl 4, 11/29/2024, 39,683 mi, P133B, RO 57498, warranty. Cyl 3, 01/22/2026, 52,959 mi, P0673/P06C7/P133A, RO 100951, I paid $713.38. Cyl 2, 08/26/2026, 57,466 mi, P06C6/P0672/P1339, RO 115953, GM under N232430460. The first three came within 39 days and 1,033 miles. Every RO documents the same finding: high internal resistance in the plug, circuit tests good. The failure is internal to the plug. Glow plug failure on a diesel causes hard starting, extended cranking, no-start in cold weather, and startup misfire - risk of being stranded or unable to start. GM has documented this defect three times: PIP5762 (12/2020), TSB 22-NA-027 (2/2022), Special Coverage N232430460 (1/2024). All name an inadequate camshaft housing cover baffle plate weld, and all limit the remedy to cylinder 2. On the recorded walkaround for RO 115953 the tech stated my engine serial falls inside the affected population and my earlier failures were probably the same condition. GM replaced only the glow plug. The camshaft cover GM identifies as the cause is still installed; GM quoted me $5,100 to replace it at my expense. Four of five failures were on cylinders 1, 3, 4 and 6, outside that scope. If the bad weld passes oil into the PCV and intake path rather than only the cylinder 2 glow plug well, ingested oil would reach other cylinders. No RO shows anyone inspected the intake tract, charge piping, cooler, PCV separator, a removed plug, or a glow plug well. I ask ODI to examine whether the cylinder-2-only scope of N232430460 is under-inclusive, whether replacing the plug while leaving the cause installed is an adequate remedy, and whether repeated internal failure of part 24000504 warrants a recall.