GMC Sierra Complaints

15,732 consumer complaints on file.

#11774342October 29, 2026
FUEL/PROPULSION SYSTEM
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 NHTSA to review this issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774349October 29, 2026
ENGINE, UNKNOWN OR OTHER
I have repeatedly experienced a noticeable exhaust odor inside the cab while operating the vehicle\. The condition is particularly pronounced during cold weather when the vehicle is idling\. Under these circumstances, the exhaust smell inside the passenger compartment is distinct and concerning\. I have taken the vehicle to two separate General Motors dealerships in an effort to identify and resolve this issue\. On both occasions, I was advised that the vehicle was fine\. Despite these visits, the problem remains unresolved, and I continue to experience exhaust fumes inside the cab under the conditions described above\. My concern is that exhaust gases may be entering the passenger compartment, potentially exposing the driver and passengers to harmful emissions, including carbon monoxide\. Because carbon monoxide cannot be detected by smell, the presence of an exhaust odor does not establish whether carbon monoxide is present or at what concentration\. However, the recurring odor warrants a thorough investigation to determine its source and whether a potentially hazardous condition exists\. I am concerned that the issue may not be adequately identified during routine dealership inspections if the vehicle is not evaluated under the specific conditions in which the symptoms occur\. The fact that two dealerships have indicated that the vehicle is operating normally does not resolve my concern, particularly because the symptoms continue to occur\. I am requesting that the National Highway Traffic Safety Administration review this complaint and determine whether further investigation is warranted into the possibility of exhaust gases entering the passenger compartment of this vehicle\. I would appreciate consideration of whether this condition could represent a safety\-related defect that may affect other vehicles of the same make, model, or model year\. I have made reasonable efforts to address this matter through authorized GM service facilities.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774370October 29, 2026
ENGINE
My 6.2 motor in my 2023 GMC AT4 truck has blown up. As part of the recall that GM has on this motor it passed the "pico test" at around 50k miles or so ( I can provide the paperwork) and then this past week with 63k miles or so the engine developed a miss and eventually by the time I got it to the dealer there was a significant "engine knock". The service center called the next day and said there was definitely a engine failure and I was lucky to have made it to the dealer. The vehicle is at the dealer waiting on a new engine. I was quoted 2 weeks but we are passing that time frame now. GM needs to be held accountable for this mess.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774398October 29, 2026
FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING, FORWARD COLLISION AVOIDANCE: WARNINGS
I am filing a formal safety complaint regarding my 2026 GMC Sierra 2500HD Duramax (VIN [XXX]; 32,607 miles). While driving at highway speeds with Adaptive Cruise Control engaged, the truck intermittently applies the brakes suddenly and forcefully with no vehicle, pedestrian, or obstruction apparent in the roadway. On some occasions it decelerates from my set cruising speed to nearly a complete stop without my braking input or warning. This creates an immediate risk of a rear-end collision, particularly in highway traffic. These events have occurred repeatedly. The brake rotors now exhibit warping or vibration, which I suspect may be related to the repeated severe braking; the cause has not been established. My previous 2025 GMC Sierra 2500HD Duramax experienced similar unexplained braking. I reported concerns but did not receive a satisfactory investigation and traded it at approximately 35,000 miles, believing the issue was isolated. The 2026 truck's behavior is worse. I purchased another GM truck without these features to maintain dependable transportation because I do not consider using Adaptive Cruise Control on this vehicle safe. I have located seven distinct online owner reports of similar unexpected braking in recent GMC Sierra and related Chevrolet Silverado trucks, including reported NHTSA complaint XXX; these reports have not been independently verified as the same defect. I request that NHTSA investigate potential false detection or unintended braking commands involving Adaptive Cruise Control and related systems on 2024–2026 GM trucks, obtain GM engineering and warranty records, and evaluate the risk to drivers and following traffic. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774468October 29, 2026
ENGINE
This is a follow up to my recent safety concern on my 2025 GMC Sierra 1500 with the 6.2 engine. Dropped off my vehicle to our GMC service dealer on 10/22/2026 - Oil change and 15K mile check up was getting close. Mileage at drop off was 14,278 and the engine was still making sounds/noise and getting louder. Asked the service advisor to check for metal in the oil or filter. Based on their service review and advisors response, metal was found in the oil filter and engine is ticking. Service department sent information to GM rep for further actions needed. Dealer rep stated that I need a new engine due to this new found issue. Waiting for response from a GM representative at this time. Truck is in my garage at home. I remain very concerned about driving this vehicle at this time. Just called the dealership as I have not heard of any follow up yet. Call went to voice mail of my service advisor. 6.2 Engine is ticking and metal has been found in the filter. Please add this to my original concern on this VIN #.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774503October 29, 2026
Carry Handle, Shell, Base, Insert, Padding
the styrofoam part on the side rest area, is broken .. When cleaning and setting back together, shouldn’t be a problem. Wish it was a different material, since my baby needs to be protected from that. Also putting it in the car, we all touch that part and it’s not so sturdy. When we hit the brake, we held it for extra security and noticed it broke when we got home, and i unassmebled it to check.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774164October 28, 2026
STRUCTURE:BODY
Subject: Complaint — 2024 GMC Sierra 1500 Denali, Upper Grille Deflector Detached at Highway Speed. To the Office of Defects Investigation, I’m filing this complaint regarding my 2024 GMC Sierra 1500 Denali. While driving on the freeway at approximately highway speed this afternoon, xxx, the upper grille trim piece located above the grille and in front of the hood spontaneously detached from the vehicle with no warning and no prior impact. It created a road hazard for other motorists. This matches the failure pattern described in Recall Query RQ26003, opened xxx, covering 2022 through 2024 Sierra 1500s. My truck is a 2024 and is not covered by Recall 25V-060, which only addressed certain 2022 models. I’m concerned the defect is not limited to the originally recalled population, and that the 2025 remedy may not have resolved the underlying attachment-point failure. I request that NHTSA include my vehicle and all similarly affected 2024 trucks in any expanded recall or investigation, and that GM be required to provide a free repair. Vehicle: 2024 GMC Sierra 1500 Denali. VIN:xxxxxxxx. Mileage: 64,952. Date of failure: xxx. Location: [XXX]. Thank you. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774171October 28, 2026
ENGINE AND ENGINE COOLING
The contact owns a 2024 GMC Sierra 1500. The contact stated that the vehicle was repaired under NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the recall repair failed to prevent a failure from occurring after passing the PICO Test. The contact stated that while driving 20 MPH, there was an abnormally loud metal clashing sound coming from under the hood. The vehicle was taken back to the same local dealer where it was test-driven, and the vehicle failed the new PICO Test. The failure mileage was approximately 23,400.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774174October 28, 2026
UNKNOWN OR OTHER
I a filing a safety complaint regarding my 2023 GMC Sierra1500. While, driving, the front hood shield/trim piece unexpectedly detached from my truck and flew off into traffic. This occurred on a freeway and could have caused a serious Collison. This is a hazard that this could detach without warning. I believe it is defective. Other models have had a recall on this part and I believe this model should as well
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774198October 28, 2026
ENGINE
My truck's engine failed in April 2026 and was replaced. Approximately 7,000 miles later, the replacement engine failed as well. After bringing the vehicle to the dealership for another engine replacement, the newly installed engine seized during the dealer's test drive before the repair could even be completed. As a result, I am facing additional delays and have been without a reliable vehicle for an extended period.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774225October 28, 2026
UNKNOWN OR OTHER
2021 GMC 3.0 Diesel have coolant control valve issues. GM has a special coverage for them under Special Coverage N252508341. That coverage covers my year make and model. I have an open case with GM under GMC Customer Assistance opened case 116070735. GM is refusing to cover it due to this cited email. "After reviewing the vehicle information, we determined that Special Coverage N252508341 does not apply because it is not associated with the vehicle identification number (VIN) on your vehicle." I had the dealership and GMC customer service confirm this. GMC told me to request goodwill assistance at the dealership which the service provider had never heard of before. I can provide all documentation needed. I had recurring P1098, followed by a reduced engine power warning and unusually loud radiator fans. I figured it may be the coolant control valve and found Special Coverage N252508341. I created an open case with GM and took it to the dealership. The dealership was ambiguous about the issue and quoted me over 2,000 dollars just for further diagnostics citing "Coolant" and "Valve" in the documentation. They also said once they find the issue it would be "more." I took it to a 3rd party mechanic for an actual understanding of the issue. The mechanic found that the issue was the coolant control valve, which I have in documentation, and recommend a clear understanding of the repair and quote for the repair.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774246October 28, 2026
SERVICE BRAKES, HYDRAULIC
The contact owns a 2015 GMC Sierra 2500. The contact stated that while driving 55 MPH uphill, the vehicle went into LIMP Mode and the vehicle hesitated. A dealer contacted. The vehicle was taken to a dealer and was diagnosed with brake booster failure. The brake booster was replaced and the vehicle was repaired. The manufacturer was notified of the failure and informed the contact that the vehicle was not under recall. The approximate failure mileage was 131,208.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774252October 28, 2026
UNKNOWN OR OTHER
Purchased new and professionally installed and used for almost 3 years without issue. Driving on highway. Approx 75MPH. Cover was fully closed and locked into place. Nothing in bed of truck. Cover was attached to both of the safety D rings. I heard a noise, looked out rear mirror and saw the cover 10-15 feet in the air and then crash onto the highway. No one was behind me at the time or I would have likely caused a fatal accident. I immediately pulled off road. Ran back to where the cover was and had to wait for traffic to break before I could run into the highway and throw the cover off the side of the road into the woods. Cars were swerving out of the way to avoid the cover before I could get it. A few cars couldn’t get out of the way and ran it over. Luckily they were cars. If a motorcycle drove over it they would have crashed. I am very lucky no one died. Also, as you can see in the photos, the safety D rings on both sides of the bed were still intact and secured to the cover rails by the safety tether straps that were secured to the truck bed. Attached to the D rings are the safety brackets that appear to be made from a molded plastic. The brackets broke off the cover and remained attached to my truck. Potential major safety defect if the safety tether and D rings are still attached to my truck, but sheared off the heavy metal cover.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774276October 28, 2026
POWER TRAIN
I am experiencing hard gear shifting in the low gears. It is very noticeable and I have a 10-speed transmission.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774289October 28, 2026
ELECTRICAL SYSTEM, VEHICLE SPEED CONTROL, LANE DEPARTURE: ASSIST
Repeated failures on my 2025 GMC Sierra EV. The truck shows 'Service High Voltage Battery' and the high voltage battery makes a high-pitched hissing noise; it has thrown battery errors twice. The A/C has failed repeatedly; this summer a passenger in the truck overheated and suffered heat stroke because the A/C was not working. Super Cruise and other driver safety features consistently fail while driving. The GPS/telematics module has failed (GPS never finds a location). The truck was at Bob Howard GMC in Edmond, OK from [XXX] to [XXX] (repair order [XXX], 41 days) for the telematics module and A/C, and went back on [XXX] for the A/C and battery and is still in the shop. GM case number [XXX]. No crashes. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
1
Deaths:
0
#11774319October 28, 2026
ENGINE
6.2 liter engine failed at 59,300 miles. Being replaced right now with remanufactured engine. 2020 GMC Sierra is not part of recall but others have had problems as well
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11773937October 27, 2026
STRUCTURE:BODY
The upper front grille deflector (or chrome hood molding) on 2024 GMC Sierra 1500 AT4 with 38k miles broke off at 65 mph and hit the windshield. It could have cracked or hit a person or another car. No warning or prior issue at all. The plastic clips must have broke
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11773952October 27, 2026
ENGINE, FUEL/PROPULSION SYSTEM, POWER TRAIN
On XXX, at approximately 2:30am, about 30 hours after purchase, a 2023 GMC Sierra Denali Ultimate suffered catastrophic engine failure in [XXX] during a planned 20 hour trip. The vehicle had about 49,007 miles at purchase and 49,411 miles at the time of failure. The check engine light appeared during the trip. Over five hours into the journey, shortly after passing through a one-lane construction zone with no shoulder, the truck made noises, then lost driving power and began slowing among highway traffic. The dashboard displayed "LOW OIL PRESSURE STOP ENGINE," code P0016, and a transmission warning. I had to move into another lane to reach the shoulder. The sudden loss of propulsion at 2:30am created a serious crash risk because the truck could have been struck by nearby traffic or become disabled on the one-lane road without a shoulder. The engine had received the GM L87 recall remedy on XXX involving a change to 0W-40 oil. Despite this remedy, the engine failed while the vehicle was moving. The repair order lists replacements for the engine, radiator, oil cooler lines, intake manifold and gaskets, spark plugs and wires, water pump gaskets, high pressure fuel lines, fuel pump gasket, and battery. The GMC app currently lists a "Required Product Emission Recall" for the fuel pump power control module and states that module failure can interrupt fuel flow to the engine. However, the NHTSA VIN lookup, refreshed XXX reports zero unrepaired recalls. The reason for this discrepancy is unknown, as is whether the fuel pump recall condition contributed to the incident. I am reporting this sudden loss of driving power and engine failure despite the prior L87 recall remedy because these conditions may pose a serious safety risk. Provide Your INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774046October 27, 2026
FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING
Upon 1st start-up collision warning system light comes on and system is disabled. I shut the truck off immediately and restart it and the collision light goes off and the system functions like normal until the next shut off and restart.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11774047October 27, 2026
STRUCTURE:BODY
I was driving on a highway when the front grill deflector flew off of my vehicle and broke my driver's side windshield wiper. The incident scared me and made me jump and I'm not sure where the part went after it flew over my wind shield but it could have hit the car behind me. The part in question was part of recall 25V060. I took the vehicle to the dealership, and they said they had already completed the recall in June of 2025 and that GMC would not cover the cost of fixing it. I see there is a new query for this exact problem RQ26003.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0

← Back to GMC Sierra