GMC Sierra Complaints (2023)

567 consumer complaints on file.

#11728906April 2, 2026
POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:VALVES/VALVE BODY
The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving on several occasions at speeds above 30 MPH, the vehicle shuddered abnormally. There was no warning light illuminated during the failures. The vehicle was taken to a dealer, where it was diagnosed, and determined that the valve body needed to be replaced. The vehicle was repaired, but the failure recurred approximately six months later. The manufacturer was notified of the failure. The failure mileage was 81,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11728466April 1, 2026
FUEL/PROPULSION SYSTEM
On 18 March 2026 I was driving at night at highway speed with my family (wife, [XXX] son, [XXX] daughter, and [XXX] son) when, without any warning, my 2023 GMC Sierra AT4 with 20,700 miles abruptly and violently shuddered and reduced speed from approximately 65 mph to 30 mph uncontrollably. Shortly after the initial speed reduction the vehicle presented simultaneous alerts that it was in "reduced acceleration mode", the "emission system control" had failed, and the that the check engine light was on. Although the vehicle claimed to be in reduced acceleration mode I was unable to prevent it from continuously slowing to 0 mph. I attempted to use the accelerator to move from the left lane of traffic to the right shoulder without causing an accident. However, the vehicle violently shuddered and would not accelerate or maintain speed. I managed to maneuver around traffic and stop the vehicle on the right shoulder. Due to the unlit highway and my family's emotional state after the incident, I determined the safest course of action was to attempt to get the vehicle to a nearby parking lot. After turning the vehicle off and back on, I managed to slowly drive with my flashers on (despite the vehicle continuing to violently shudder) approximately 1 mile to a Wal-Mart parking lot. Once there I noticed I received an email from OnStar Diagnostics that my vehicle experienced a significant engine malfunction with an associated P129F code. I coordinated for the vehicle to be towed to Bill Cramer Chevrolet GMC Inc in [XXX] the following day. My vehicle had no lights, messages, or symptoms of this issue prior to it occurring. The dealership replaced the fuel pump power control module under warranty, cleared the faults, test drove the vehicle, and returned to me on 31 March 2026. The dealer mentioned they service roughly two vehicles of similar make and/or models daily for the same 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
#11728176March 31, 2026
STRUCTURE:BODY
While driving under normal conditions, a front grille trim component detached from my vehicle without any impact or external cause. The piece became airborne and struck my windshield, creating an immediate safety hazard and risk of loss of control. There was no prior damage or warning. This represents a failure of a vehicle component under normal operation and indicates a defect in materials, design, or installation. Exterior parts should not detach and become projectiles at roadway speeds. The manufacturer has been notified but has declined responsibility. Given the safety risk, this may not be an isolated issue.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11727637March 28, 2026
ENGINE
My vehicle is a GMC Sierra 1500 Duramax diesel. The vehicle experienced a failure of the DEF (Diesel Exhaust Fluid) system, which was diagnosed by the dealership as a failure of the DEF tank heater. The heater is integrated into the tank assembly, requiring full replacement of the DEF tank. As a result of this failure, the vehicle became unusable and has been out of service since March 3, 2026. The dealership confirmed that the required part is on national backorder with no confirmed availability date. This condition creates a significant reliability and potential safety concern. When the DEF system fails, the vehicle can enter a reduced power or speed-limited mode, which may occur during normal driving and could create unsafe conditions in traffic. Additionally, there appears to be a broader pattern of similar failures affecting other vehicles of the same type, combined with extended delays in obtaining replacement parts. The lack of parts availability results in extended periods where the vehicle cannot be safely or reliably operated.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11727522March 27, 2026
POWER TRAIN, ENGINE
Incident Summary: On 2/2/2026, my vehicle was serviced under Safety Recall 25V-274 at an authorized GMC dealership. The service technician performed the mandated diagnostic protocol (including the PicoScope test) and informed me that the engine had "passed" inspection. No internal components were replaced; the remedy was limited to an oil change to a higher-viscosity oil (0W-40) and a new oil filler cap. The Failure: Approximately 48 hours after this "successful" recall remedy, the vehicle suffered a catastrophic engine failure while in operation. The engine failed entirely. The vehicle lost all propulsion while in motion, creating an immediate safety hazard for myself and other motorists. Diagnostic and Risk: The failure has been confirmed by a GMC dealer, who subsequently performed a full engine and radiator replacement. In the 48-hour prior to failure, there were no warning lamps or symptoms; the vehicle had just been cleared by the manufacturer's own diagnostic tools as safe and free of defects. Systemic Concern: This incident demonstrates that the current diagnostic protocol for Recall 25V-274 is insufficient to identify terminal manufacturing defects in the connecting rods and crankshaft of the L87 6.2L V8 engine. The "remedy" of higher-viscosity oil failed to prevent the exact catastrophic loss of propulsion the recall was intended to address. The replaced engine is available for inspection upon request by the NHTSA Office of Defects Investigation.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11727604March 27, 2026
STRUCTURE:BODY, STRUCTURE:EXTERIOR TRIM
The grille deflector flew off while driving. The same exact problem the 2022 sierra had as described in N242490120
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726902March 25, 2026
ENGINE
Our truck had just passed 60,000 miles when the engine seized. The recall procedure was completed in January, and the engine passed the test at that time. We were also using the recommended 0W‑40 oil. Despite following all guidelines, the engine still failed. This shows that the procedure GM has outlined is not sufficient to determine whether an engine is actually in good condition.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726656March 24, 2026
ENGINE
While traveling northbound on I‑65 on Saturday, 1/31, the 6.2L V8 engine in my 2023 GMC Sierra AT4 experienced a sudden and complete internal failure. My husband was driving and I was in the vehicle with him when the engine lost all power without any warning lights, messages, or prior symptoms. We were only able to coast into a very busy on‑ramp merge lane before the truck died completely, leaving us stranded in an active traffic area for over two hours on one of the coldest days of the year, which created a significant safety risk for both of us and for other drivers. My truck was towed to the dealership. They inspected the vehicle, confirmed it was a full engine failure, and replaced the engine under warranty. The failed engine only had just over 37,000 miles on it at the time of the incident. GM was notified through the dealer’s warranty process. No other agencies have inspected the vehicle.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726850March 24, 2026
UNKNOWN OR OTHER, STRUCTURE:EXTERIOR TRIM
I was driving on the highway at about 80 miles per hour and all of the sudden, a piece of the front grill detached and flew off, hitting the top of the of the roof.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726395March 23, 2026
ENGINE
Based on the critical recall and safety concerns for this known issue for the 6.2 L87 Engine failure I am highly concerned that it takes over 171 days to just get an appointment to look at this issue. This is further compounded by the fact I put approx 800-1000 miles a week on my truck and now am worried about having an accident or blowing my truck up.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726497March 23, 2026
STRUCTURE:BODY
The top part of the front grille fell off while driving
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11726558March 23, 2026
ELECTRICAL SYSTEM
The rear vision safety camera failed. A Red Triangle with a camera icon appeared on the infotainment screen when the vehicle was put in reverse. After testing and diagnosing the issue, the dealership determined that the rear camera suffered an internal failure and had to be replaced. The part was replaced on 3/23/26 but the dealership did not give me the failed camera back. There was no advance notice or warning leading up to the failure.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11725938March 20, 2026
STRUCTURE:BODY
The grill deflector flew off the truck doing 80mph on hwy130 in Austin, Texas.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11724873March 17, 2026
POWER TRAIN, ENGINE, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING
My 2023 GMC Sierra has 60,571 miles for a while now while driving the transmission slips and slams into gears. Recently driving with my kids in the car on highway going 70mph the back brakes locked up multiple times, so scary and dangerous while driving. I now currently have a code P-0747 in the system.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11724595March 16, 2026
UNKNOWN OR OTHER
Was driving down interstate and the top of my grill came off and smacked my windshield. Also, my tailgate opens on its own but the grill is the main safety issue. I have seen where they already have recalls on 2022s and earlier due to chrome grill coming off but mine is a 2023 and gm is refusing to honor it when it is obviously the same issue. Was very scary and could have caused a wreck as grill ended up on interstate being thrown around by vehicles. GM stated I would need recall added to my VIN in order for them to pay for it. Thank you!
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723825March 12, 2026
ENGINE
Engine with leas than 40,000 miles is consuming one (1) quat of oil every 2,000 miles. GM dealership showed me the internal GM service update stating the accepted rate of oil consumption for engines uses in the vehicles referenced is 1qt per 2,000 miles. That may seem acceptable because GM put it in a notice to dealerships but I assure you the end consumer would never buy this engine if this was explained prior to purchasing. There is a reason new cars to not consume oil (at least not at a level you need to add oil between oil change intervals) at this rate. Long term wear and tear on the engine - note Gm offered a warrantee covering 100,000 miles, which is nice but the problems will become more severe over time and miles. I consider this borderline criminal as it will surely cause engines to lock up.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723729March 11, 2026
FUEL/PROPULSION SYSTEM, ENGINE
While driving home from Phoenix on Hwy 95, 30 Miles out of Tonopah on the way to Reno engine propulsion and the complete engine failure occurred while driving at 75 mph. No warning at all. No cell service, had to use Onstar to be our savior. Thank God they sent a tow truck, although my wife and I with 2 dogs had to wait 4 hours for the tow truck, while semi’s rolled by us going 80 mph. Dealer performed diagnostics on my truck and has to replace the engine due to engine failure. I had the recall completed in September with the new approved oil and cap. I know this is an ongoing problem with GM’s 6.2 engine. Complete engine failure while driving at 75 mph. No engine warning sign. Screen went blank. I will no longer trust this truck or have any confidence in the truck once I get it back. I sure hope GM pays for this. This has caused me endless anxiety.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723265March 10, 2026
SERVICE BRAKES, ELECTRICAL SYSTEM, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING
This complaint involves a sudden failure of my vehicle’s Anti-Lock Braking System (ABS) and Forward Collision Warning system, both of which are critical safety systems. While driving my [XXX] son to school, multiple warning lights suddenly appeared on the dashboard without any prior indication of a problem. The vehicle displayed a warning message instructing me not to exceed 36 miles per hour, and several system alerts activated simultaneously, my ABS brake system failed and a transmission failure warning. These issues appeared suddenly while the vehicle was in normal operation. Prior to this incident, the vehicle had been functioning perfectly. The evening before, I had driven the vehicle to pick up my son from wrestling practice with no issues. The following morning, during a routine trip to school, these critical safety warnings appeared without warning. Because the warnings involved the braking system, I immediately took the vehicle to Beach Buick GMC for inspection. The dealership diagnosed the issue as a software failure affecting the braking system and informed me that the vehicle required a software update and system download in order to restore proper operation of the brakes and related safety systems. I was required to pay over $300 for this repair because my vehicle is approximately 3,000 miles outside of the warranty period. However, I believe a failure involving the braking system and safety warnings should not occur suddenly in a properly functioning vehicle and should not be treated as a normal maintenance expense. I contacted **General Motors customer service to ask why a failure involving a critical safety system would not be covered or investigated further. The only explanation provided was that the vehicle was outside of the warranty period. I requested a written explanation of their decision for my records, but I was told that providing written explanations is against company policy. I have more to say but I am out of characters... INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMA
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723343March 10, 2026
ELECTRICAL SYSTEM
The contact owns a 2023 GMC Sierra 2500. The contact stated that on several occasions, after the vehicle had been parked for approximately two days, the vehicle failed to start. The vehicle was jump-started and taken to a dealer three times, where it was diagnosed and determined that the battery needed to be replaced. The vehicle was repaired three times, but the failure persisted. The manufacturer was notified of the failure, and a complaint was filed. The failure mileage was 33,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723417March 10, 2026
POWER TRAIN
While entering the freeway at approximately 45 MPH not towing the rear wheels locked for a second, truck went into the Limp mood, and dash said reduce speed, service transmission. Dealer pulled codes, P0700 and P0747...the order says cause document #6998510."replace spacer plate, check balls and valve." Correction: DTC P0747 set Dealer told me the put the new updated valve in but I don't see that on the repair order? I asked about the GM extended warranty ( I think it's 10 years, 150,000 miles). they said it didn't apply to my vehicle?
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0

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