GMC Complaints

Safety Complaint – 2025 GMC Sierra 1500 Tailgate While driving our 2025 GMC Sierra 1500 and towing a trailer, the tailgate unexpectedly opened and dropped down while the vehicle was in motion. No one touched the tailgate button, key fob, or any other controls to activate the tailgate. We were unaware that the tailgate had opened. When we made a turn, the trailer contacted the tailgate and crushed/damaged it. This occurred without any intentional activation of the tailgate release. We believe this presents a significant safety concern because an unexpectedly opening tailgate while driving, especially while towing a trailer, could result in property damage, loss of cargo, or a more serious accident. We are requesting that this issue be investigated to determine whether there is a defect with the tailgate latch, release mechanism, or electronic controls on the 2025 GMC Sierra 1500.

while driving my 2023 GMC Sierra AT4 at highway speed, the front grille piece (GM part 84957848, roughly 3 feet or longer) detached from the vehicle without warning and flew off into the roadway. The piece landed on the shoulder rather than in a travel lane, but given its size, it could easily have struck another vehicle or caused a serious accident if it had landed differently. I was then forced to stop on the highway shoulder to retrieve the part, which put me in an unsafe roadside situation with traffic passing at highway speed. This part had all its retaining clips still intact, indicating a failure of the part/mounting itself rather than a missing clip or improper installation. part number 86274905

Fuel pump control module and or the in tank fuel pump failed and or isn’t making proper connection for car to run correctly. Safety was put at risk as car came to abrupt halt while driving. Driver was outside of vehicle at busy intersection for vehicle diagnostics and battery jump. Battery was removed and new battery installed yet problem persists. Not confirmed by dealer but code is as follows (p129F). Maintenance performed by owner;Code reader used for diagnostics, new battery installed. Problem persists. Car started, drove and stumbled to then die. Check engine now displays.

The piece in front of the hood detached and flew off while riding down the highway.

XXX Pulling into Mason Park - Truck Shot down while driving. Went into Park (immediate stop) 2 of my Kids were in the truck at the time. Restarted truck and loud Noises. Immediately backed into parking space shut down and towed. Sent to dealership XXX Called spoke co/ Mark. [XXX] had tech. look at truck. expressed My concerns and Should Never occurred @ 6788 miles. Expressed Something Needs done. Recommend contact GMc. - Call GMC, Crated a Case #XXX. Engine replaced after 2 months. No one checked the transmission or had explained why it went into park while in operation.Refused to look at any other concerns. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

While driving my 2021 GMC Yukon Denali with the 6.2L L87 V8 on a high-speed highway near Somers Point, New Jersey, the vehicle suddenly began bucking and the accelerator stopped responding normally. The vehicle rapidly lost propulsion while I was surrounded by highway traffic and approaching a bridge. I was fortunate to get the vehicle onto the shoulder before reaching the bridge. I was then stranded on the shoulder of a high-speed highway, where the disabled vehicle created a serious safety risk to me and other motorists. The engine shut down and would not restart. It initially cranked as though it was attempting to start, but it did not start. I received a diagnostic alert stating, “Service the engine and transmission system immediately.” The vehicle required a tow. The tow operator later reported that it appeared locked up and could not be shifted into neutral. The vehicle has approximately 77,000 miles and has been serviced regularly. Its most recent oil-change sticker indicated the next oil service was due at approximately 81,000 miles. While safely pulled over, I checked the engine-oil dipstick and confirmed that the engine had oil, with oil visible across the dipstick’s normal measuring area. Despite this vehicle having the 6.2L L87 engine and experiencing a sudden loss of propulsion and no-start condition, its VIN does not currently appear in GM’s public recall lookup for the existing L87 recall. The vehicle is being transported to an authorized GMC dealer, and the precise failed component has not yet been confirmed. This sudden loss of propulsion created an immediate risk of a serious highway collision, particularly because it occurred immediately before a bridge. I understand NHTSA is investigating continuing L87 engine failures, including failures involving vehicles outside the original recall population. I am submitting this complaint so this incident is formally documented and considered as part of that investigation.

Driving down [XXX] in [XXX] the engine seized and blew every major electrical fuse. The suv was in the center lane of [XXX] at rush hour unable to be put in neutral and rolled to safety. SUV was towed home then to dealership for confirmation. Engine and all wiring were replaced. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

After the initial recall inspection was performed, I was informed that my vehicle was not affected. Subsequently, the vehicle experienced a catastrophic engine failure while traveling westbound on [XXX] near [XXX], approximately one mile from [XXX]. While traveling at highway speed, the vehicle suddenly began losing speed and power. I was positioned between two semi-trucks, creating an extremely dangerous situation. At first, I looked to see if I was traveling uphill because of the unexpected loss of speed. I then pressed the accelerator in an attempt to maintain highway speed. The vehicle abruptly downshifted and the engine RPM increased dramatically. Immediately afterward, warnings appeared on the instrument cluster, including “Engine Oil Temperature High” and instructions to pull over and allow the vehicle to cool down. The vehicle continued to lose power, creating a serious risk of collision due to the surrounding highway traffic. The vehicle was subsequently towed to Findlay GMC, where it was inspected and diagnosed with a failed engine. The engine was ultimately replaced. This failure occurred after the vehicle had been inspected under the recall and I had been advised that it was not affected. I am concerned that my vehicle may have been incorrectly excluded from the recall or that the recall does not adequately identify all affected vehicles. The sudden loss of propulsion at highway speed presented a significant safety risk and warrants further investigation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Engine stopped working while driving 65 mph on I435 Kansas City. Engine failure had to pull over in 3 lane traffic to get off of roadway. Engine just stopped working. Had towed to GM dealer who performed full engine replacement. 6.2 L . No warning. Just stopped working. Safety traveling on 3 land highway engine stopped with no warning had to work way over the shoulder with no engine.

My vehicle was with ANCIRA GMC Boerne for approximately three weeks where they replaced the transmission control system/module, the centralized OnStar module, and diagnosed both rear screens for replacement. Approximately one month after getting it back, at only 49,800 miles, I experienced a complete loss of propulsion. The vehicle shut down while I was driving. Given the recent transmission repair and the fact that this failure occurred while the vehicle was in motion, I no longer have confidence in the safety or reliability of this vehicle. I have young children riding in this vehicle daily and I’m not comfortable accepting another repair and simply being told it’s safe to drive.