GMC Sierra Complaints

15,732 consumer complaints on file.

#11718353February 16, 2026
ENGINE, VEHICLE SPEED CONTROL
While driving I get a reduced acceleration warning on my dash cluster, drastically reducing horse power. My check engine light came on. This has happened before. I checked the code and it was a P1098 code. After researching I found out it was the Engine coolant control valve. My fan is constantly running. This issue is ongoing. This seems to be a common occurrence with my vehicle year.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718072February 15, 2026
POWER TRAIN, ENGINE
Odd noise from bell housing area at 1200 miles that went with engine rpm. Took the truck in to the dealer and they said they couldn't recreate it but to bring it back in if it returned. Jan 27th at 5200 miles on the truck, I was driving down the highway at 60mph and got a reduced acceleration message on the dash along with a check engine light. Brought it to the dealer and was informed it was a bad thrust bearing and needed and engine and turbo replacement. Still waiting for the truck to be done.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718107February 15, 2026
AIR BAGS
Air bag front impact sensor are no longer available from manufacturer. Airbag system in inoperable.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718135February 15, 2026
POWER TRAIN
Truck had 3 momentary rear wheel lock ups on the highway from 41 - 52 mph.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718159February 15, 2026
POWER TRAIN
The truck keeps wanting to engage two gears acceleration and deceleration and still is happening i have taken it to the dealership an they can not find a problem took it home an its happening again so now its back at the shop now I'm waiting to hear back from them so this is the second time to the dealership
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718162February 15, 2026
POWER TRAIN
A couple times I heard loud clanking coming from rear brakes. One time in particular I was trying to stop and it felt line someone had ran into my truck but must have been the rear wheel locking up
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11718047February 14, 2026
ENGINE
Catastrophic engine failure at 62,445 miles. Dealer state excessive oil in cylinder 7, ring failure. Recommendations; remove and replace engine.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717814February 13, 2026
FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING
On 3 separate instances the past few months the truck slammed on brakes for no apparent reason. And 2 separate times the past week or so the truck suddenly and uncontrollably accelerated — first at gas a station convenience store and almost ran over old lady, secondly while waiting line on arterial entrance ramp!
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717922February 13, 2026
ENGINE, POWER TRAIN, ELECTRICAL SYSTEM
The contact owns a 2024 GMC Sierra 1500. The contact stated that while driving at 67 MPH, the transmission shifted to neutral(N) unexpectedly. In addition, the vehicle failed to accelerate as intended while depressing the accelerator pedal. The contact attempted to drive the vehicle off the road. A passerby slowed down and allowed the contact to move over to the side of the road. The engine seized, and the vehicle stalled between the shoulder and the line of the left lane. The check engine warning light illuminated, and the messages "Battery Low" and "Reducing Features to Save Battery" were displayed on the instrument panel. The contact called a friend who towed the vehicle to the dealer. The dealer was informed that the engine had failed and needed to be replaced. The vehicle remained at the dealer unrepaired. The contact stated that due to the failure, the contact no longer felt safe while driving the vehicle. The manufacturer was notified of the failure. The failure mileage was 52,680.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717926February 13, 2026
ENGINE, FUEL/PROPULSION SYSTEM, UNKNOWN OR OTHER
Component / System Failure The exhaust system, specifically the exhaust manifolds and previously the EGR system components, appear to have failed or malfunctioned, allowing exhaust gases to enter the passenger cabin. The dealer initially replaced the EGR cooler diverter on December 23, 2025. However, the condition persisted. On February 3, 2026, cracked exhaust manifolds were identified by the dealership, and a major front-end teardown was advised to complete the repair. The vehicle is currently available for inspection upon request. ⸻ How Safety Was Put at Risk The malfunction allowed exhaust gases, including carbon monoxide, to enter the passenger cabin during vehicle operation. Carbon monoxide readings inside the cabin reached up to 50 parts per million (ppm) while driving. Carbon monoxide is a toxic gas that can cause: •Headaches •Dizziness •Impaired concentration •Nausea •Vision disturbances Because carbon monoxide is odorless and colorless, this presents a significant safety risk, particularly at highway speeds where driver alertness is critical. The exposure occurred while operating the vehicle in normal driving conditions. This created a potential risk of driver impairment and increased risk of collision. ⸻ Has the Problem Been Reproduced or Confirmed? Yes. The vehicle was presented to the dealership three times for the same exhaust intrusion concern: •December 16, 2025 •December 29, 2025 •February 3, 2026 During the February 3 visit, the dealership confirmed cracked exhaust manifolds requiring major disassembly for repair. The carbon monoxide readings were observed during vehicle operation. The exhaust odor and intrusion symptoms were consistently present following the first attempted repair. ⸻ Has the Vehicle Been Inspected by Manufacturer or Others? The vehicle has been inspected by the authorized dealership on multiple occasions. Two manufacturer customer care cases were opened.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717754February 13, 2026
ELECTRICAL SYSTEM, ENGINE, POWER TRAIN
The vehicle has experienced repeated incidents of sudden reduced engine power and loss of acceleration while driving. On multiple occasions, while traveling at highway speeds, the vehicle failed to respond normally to throttle input and would not accelerate as commanded and loss of power steering making it difficult to turn the steering wheel and apply brakes. One incident resulted in throwing my truck off the road and luckily we nearly avoided a multi car collision and potential pile with my wife, 8yr old daughter and newborn son in the vehicle at high speeds up to 60/70+ mph but despite avoiding a major life threatening accident to us and other drivers, resulted in striking objects, glass and debris on the side of the road causing damage to my vehicle and then sliding to a complete stop in the ditch off the highway. This creates a hazardous driving situation, particularly when merging into traffic or attempting to maintain speed with surrounding vehicles, increasing the risk of collision. The malfunction appears related to the engine, electrical system, and powertrain. During at least one dealership visit, the reduced power condition was recreated and confirmed by service personnel. However, despite multiple warranty repair attempts, the issue continues to reoccur intermittently. Warning messages have appeared at times, including reduced engine power notifications and check engine indicators, though the condition has also occurred without advance warning. The intermittent nature of the defect makes it unpredictable and unsafe. The vehicle has been out of service for more than 30 cumulative days for warranty-related defect repairs related to this and other electrical issues. Multiple repair attempts have not permanently corrected the condition. The vehicle remains available for inspection upon request. Due to the unpredictable loss of acceleration and prior safety incidents, there are ongoing concerns regarding safe operation of the vehicle.
Crash:
Yes
Fire:
No
Injuries:
0
Deaths:
0
#11717761February 13, 2026
FUEL SYSTEM, GASOLINE
The contact owned a 2019 GMC Sierra 2500. The contact stated that on several occasions while driving at undisclosed speeds, the vehicle lost motive power. There was no warning light illuminated. The vehicle was restarted; however, the failure recurred. The vehicle was taken to an independent mechanic, where it was diagnosed and determined that the rear fuel tank had failed and needed to be replaced. The vehicle was not repaired. The dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 65,580.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717465February 12, 2026
ENGINE
My GM Dealership completed the GM 6.2 Engine Inspection and recommended Oil Replacement as part of the 6.2 Engine Recall. Roughly 5,000 miles after this service, the engine failed. I attempted to accelerate from 45-65 miles per hour while getting on the highway, and the engine seized up. I was able to coast/steer the vehicle to the side of the road. The vehicle's starter could not crank the engine. I had the vehicle towed to the shop where the dealership confirmed the engine had seized. The dealership and GM replaced the engine under a warranty repair. I am making you aware of this situation, as the manufacturers suggested solution to the engine issue (The Change in Oil Type, Filter and Cap) did not prevent the engine from failing.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717477February 12, 2026
ENGINE
The contact owns a 2019 GMC Sierra 1500. The contact stated that the vehicle made an abnormal rattling sound while idling. Additionally, while driving at 45 MPH, the message "Reduced Power" was displayed, the check engine warning light illuminated, and the vehicle stalled. The contact was able to coast to the shoulder of the roadway. The vehicle failed to restart and was towed to the dealer, where it was diagnosed and determined that there was no compression in the engine. The dealer determined that the engine needed to be replaced. The dealer advised the contact that the repair was not covered because the VIN was not under recall. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 126,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717546February 12, 2026
POWER TRAIN
My 2026 GMC AT4 3.0L Duramax had a catastrophic engine failure on Sunday, February 8, 2026. It went into reduced acceleration and also fault code PO6DD. Thankfully I was not on a highway. The truck would not run over 45 MPH on flat ground, and then by the time I got it to a safe location 5 miles away it would not run over about 30MPH. This obviously resulted in the truck being towed to a dealership. I have been told the entire engine will be replaced. Upon further reading, I suspect this is a thrust bearing failure that is a well-known issue in this LZ0 Duramax engine. What I have read, this issue is occurring mostly on trucks built from May-Sept 2025, and my truck has a 7/2025 build date. This could have been major safety hazard if the engine had failed in a major freeway/highway.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717554February 12, 2026
ENGINE
2025 GMC Sierra 1500 has had 2 engine failures since purchase date June 2025. Engine failed on a road trip with my family, leaving me stranded for hours. After the problem being resolved, engine failed once again after 5 months. On the dash it said loss of power and wouldn’t crank to turn ON
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717560February 12, 2026
UNKNOWN OR OTHER, ENGINE
I own a 2024 GMC Sierra Denali Ultimate 2500HD diesel that has been out of service for 52 days due to an oil cooler / service bulletin related failure. The vehicle is under warranty. The required replacement part is on national backorder and, as of today, has not shipped. The current estimated ship date is February 17. During this time, neither the dealership nor GMC has provided proactive communication. I have had to repeatedly contact them for updates. This extended inability to repair a critical component, combined with the lack of parts availability and communication, raises concerns about the reliability of this system and the manufacturer’s ability to support safe operation of the vehicle in a reasonable timeframe. The truck is my primary vehicle and is intended for towing and transportation. Being unable to repair it for nearly two months due to parts unavailability presents a significant safety and reliability concern.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717562February 12, 2026
ENGINE AND ENGINE COOLING
The contact owns a 2022 GMC Sierra 2500. The contact stated that the engine was making an abnormal rattling sound on cold starts. There was no warning light illuminated. The vehicle was taken to the dealer, where the front muffler exhaust baffle was replaced; however, the failure persisted. The vehicle was taken back to the dealer, where the contact was informed that the rattling sound could not be heard; however, the contact stated that the rattling sound had become louder, and other individuals were able to hear the rattling sound. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717579February 12, 2026
ENGINE
Had a P1098 code. The truck was diagnosed by a certified technician. Found to have a failing coolant control valve. GM has issued special coverage for this known failure. Special coverage is not including the VIN for this truck although it falls in the criteria for model, year, and engine model.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11717655February 12, 2026
POWER TRAIN
I am submitting this complaint regarding a recurring transmission issue in my vehicle. The transmission consistently jerks and shifts erratically, particularly in the morning during initial operation when at cruising speeds of about 50-75 mph. This behavior occurs when the transmission temperature is below approximately 100°F and happens on a daily basis. The gear changes feel harsh and abrupt, kind of like it doesn’t know what gear to be in its raising concerns about both drivability and long-term transmission reliability. I brought the vehicle to an authorized dealership for inspection. After evaluating the issue, the dealer informed me that the behavior was due to the vehicle being in “Sport Mode.” However, this explanation does not resolve the concern, as the severity and consistency of the jerking appear abnormal and occur regularly under the same temperature conditions. Given the persistent nature of this problem and its potential safety implications — especially during acceleration and low-speed driving — I am requesting that this issue be formally documented and investigated. Thank you for your attention to this matter.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0

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