GMC Sierra Complaints

15,732 consumer complaints on file.

#11758921August 23, 2026
ENGINE
Truck has the 6.2 Litre engine,failed.GM won't do anything to fix or replace the engine.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758936August 23, 2026
SERVICE BRAKES
On [XXX], while driving my 2025 GMC Sierra 1500, VIN [XXX], near [XXX], California, the vehicle suddenly experienced a severe brake failure while traveling on a public roadway. When I attempted to apply the brake pedal, the vehicle failed to brake normally and I was unable to safely stop the truck using normal braking. I was forced to reduce speed and allow the vehicle to coast until I was able to enter a side road and bring the vehicle to a stop. I was extremely fortunate that traffic conditions were light at the time. A vehicle traveling in front of me, an intersection, pedestrians, or heavier traffic could have resulted in a serious or fatal crash. After stopping the vehicle, I discovered a metal retaining ring/clip on the floor directly underneath the brake pedal area. At approximately the same time, multiple brake system failure and warning indicators illuminated on the instrument panel. I immediately contacted GMC through the vehicle's SOS system and reported the brake failure. The vehicle was subsequently towed and delivered to a GMC dealership/service department for diagnosis and repair. This appears to involve the mechanical separation or detachment of a component associated with the brake pedal assembly. I have retained the metal component, video evidence of the condition and warning lights, towing information, and dealership repair documentation. A sudden loss of braking caused by the separation of a brake pedal component presents an immediate and potentially life-threatening safety risk. I respectfully request that NHTSA investigate this failure and determine whether similar failures have occurred in other 2025 GMC Sierra 1500 vehicles. 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
#11758686August 22, 2026
ENGINE
1. What component or system failed or malfunctioned, and is it available for inspection upon request? The engine oil consumption system/engine is experiencing excessive oil consumption. My 2021 GMC Sierra is equipped with the 6.2L engine, and the engine is consuming oil at a rate that I believe is abnormally high. The vehicle and engine are available for inspection upon request. I am also concerned that my vehicle may be affected by an engine-related recall or safety campaign associated with this engine. When attempting to verify the recall status, the system appears to have an error and is not identifying my vehicle. I am requesting that the vehicle’s VIN and engine configuration be manually verified against all applicable recalls and safety campaigns. 2. How was your safety or the safety of others put at risk? The excessive oil consumption creates a potential safety concern because I am concerned that the engine could become critically low on oil while I am driving, potentially resulting in engine damage, loss of power, or complete engine failure. This could occur while traveling at highway speeds or in an area where it may be difficult or unsafe to stop. I regularly travel with my family, which increases my concern about the possibility of an unexpected engine failure and the potential risk to my passengers and other motorists. 3. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. I previously addressed this issue with Newton Chevrolet in [XXX], and later took the vehicle to Malcolm Chevrolet in [XXX], after continuing to experience concerns about excessive oil consumption. Malcolm Chevrolet tested the vehicle and confirmed that it is consuming oil at an excessive rate. The prior visit to Newton Chevrolet and the subsequent confirmation by Malcolm Chevrolet demonstrate that this concern has been reported and evaluated by more than one dealership. 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
#11758744August 22, 2026
ENGINE
While driving my son to school we were driving 45 mph and the entire engine shut off and lost all power. Engine would not restart. Took it to the dealer and was told the engine was dead.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758757August 22, 2026
ENGINE
While traveling northbound on the I 10 freeway my vehicle wouldn’t accelerate once pulled over to the shoulder the vehicle completely lost all acceleration and shut off. The vehicle smelled like burning plastic and would not restart. The dealership’s reporting engine fail.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758805August 22, 2026
ENGINE
Catastrophic failure of engine while exiting the interstate.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758808August 22, 2026
ENGINE
One evening while driving home from work, the transmission warning light illuminated on my dashboard, indicating that the vehicle would soon stop. The notification specifically stated there was a transmission problem. The following morning, I brought my truck to GMC for service. After running a diagnostic, GMC confirmed an issue with the transmission. A few days later, GMC informed me that they were waiting for a replacement part to arrive. The part did not arrive for almost a month. During this waiting period, I was forced to pay for a rental car. Since my truck was still under warranty, GMC should have covered the cost of the rental car for the weeks my vehicle was awaiting repair.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758441August 21, 2026
ENGINE
At approximately 14,000 miles, the 6.2L V8 engine experienced a major failure due to a spun main bearing, which resulted in the complete replacement of the engine. The vehicle remained at the dealership for more than 60 days while the repair was completed. After receiving the vehicle back, it operated without any significant issues until approximately 30,000 miles, when the engine experienced another major failure. This second failure was attributed to the lifters, and the engine required substantial repairs and ultimately had to be rebuilt. Having two major engine failures before reaching 30,000 miles—first requiring a complete engine replacement and then requiring the replacement engine to be rebuilt—has raised serious concerns regarding the vehicle’s long-term reliability and durability.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758448August 21, 2026
ELECTRICAL SYSTEM, EXTERIOR LIGHTING, SUSPENSION
The truck when put in parking it still roll forward a little bit. Back up camera can’t not see during night time. Dealership stated they will not solve that problem and tell us to do manually by turn around look back. The suspension really bouncy but the tech stated that is normal. Spoke to other 3rd party tech they said that not normal at all.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758455August 21, 2026
UNKNOWN OR OTHER
I purchased this new 2026 GMC Sierra 1500 on 07/16/2026. Beginning shortly after delivery, the vehicle began intermittently losing ALL audio, including the audible turn-signal indication. The condition now occurs approximately once every 3–4 vehicle starts/uses. When the failure occurs, there is no audio from the infotainment system, radio, Apple CarPlay, Bluetooth, or speakers, and there is no audible turn-signal sound. Because the failure also eliminates audible driver feedback from the turn signals, I am concerned this is not simply an entertainment-system issue. The vehicle is available for inspection upon request. The vehicle was presented to Ed Morse Sawgrass Auto Mall, an authorized GMC dealer, after the condition occurred again on approximately 08/20/2026. The dealer advised me that the vehicle already has the applicable software programming and that GM is aware of the condition. The Service Manager advised me in writing that GM currently instructs the dealer to recover/reset the radio and not replace the radio or amplifier because GM is working on a permanent correction. Restarting the infotainment system, Safe Mode, disabling Quick Startup, and allowing the vehicle to completely power down have not permanently corrected the condition. A full shutdown may temporarily restore the audio, but the failure returns. There are no warning lamps or messages before the failure. The audio simply does not function when the vehicle is started. The vehicle currently has approximately 976 miles. There has been no crash, fire, injury, or fatality. I have also formally reported the condition to GMC Customer Assistance. GMC Case #108458085.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758457August 21, 2026
STRUCTURE:INTERIOR PANELS:DASHBOARD
The contact owns a 2010 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 21V053000 (Air Bag). The contact stated that while the vehicle was parked, he became aware that there was a crack on the top of the infotainment system on the dashboard. The contact stated that a month later, the vehicle was taken to a dealer for the recall repair. The vehicle was repaired, but there was a large hole approximately one to two inches in size on the driver's side dashboard near the defroster vent. The manufacturer was notified of the failure. The failure mileage was 102,928.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758525August 21, 2026
SUSPENSION
Several months ago while having my truck serviced, I asked the repair shop to inspect the ball joints on the passenger side because they would make a popping noise when turning the wheel. The shop inspected them and said that was a normal sound due tot he factory lift. Recently I was driving home and about to turn into my lane when the front passenger wheel assembly collapsed under the truck due to the a upper ball joint failure separating the brake line and loss of steering. At the time, I was only going about 25mph and the truck slid to a stop on its own. The truck has 65,000 miles on it and if this had happen at highway speeds personal injury to myself and others would have been likely. The repair cost were $7,500. Fortunately I purchased an extended warranty which covered all but $1,700 of the repair.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758571August 21, 2026
STRUCTURE
See attached document for complaint.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758601August 21, 2026
ENGINE
The engine was producing a strange noise while driving and subsequently shut off. The vehicle was towed to a GMC dealership where an inspection/testing was performed. Ultimately, I was told the entire engine needed to be replaced.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758612August 21, 2026
ENGINE, FUEL/PROPULSION SYSTEM
I bought a new GMC Sierra 1500 Denali with the 6.2L V8 engine in December of 2025. 7 months later, I was driving home from work. When the car started, it sounded a little louder, but not out of the ordinary. I started driving and got a strange rattle when I was getting on the highway at around 65MPH. I pulled off at the next exit and checked my fluids, checked under the car to see if anything was caught that was causing the rattle. All pressures and fluids were normal. I had Onstar run a system diagnostic. The diagnostic read normal. I got back on the highway and drove about 20 miles at 75mph. The rattling continued. 20 miles later, the check engine light came on. I had onstar run a diagnostic and came back stating “engine and transmission system problem” with two error codes. One code said “An issue has been detected in the Variable Valve Timing System adjust the timing of fuel delivery for more efficient engine operation”. The other code said “An issue has been detected in the Ignition System which oversees the timing and spark necessary to ignite fuel in your engine” Both error codes said to fix within one day. The GMC dealership was on the way home so I was going to stop there and see what they could do. I never made it to the dealer. About 2 minutes after the diagnostic, while doing 75mph on the highway, I hit the accelerator and the car did not speed up. The engine then shut off while I was in the left lane doing 75 mph. The electronics stayed on and the dash stated “press start to start engine.” I pulled over to the side of the highway and put the car in park and attempted to restart the engine. The engine never turned over again. I could not get the engine to start. I could not shift the car to neutral to have it rolled up on to the tow truck. My truck was towed to the GMC dealership and they are now replacing the engine under warranty. Will upload any maintenance paperwork once engine is replaced.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758626August 21, 2026
ENGINE, POWER TRAIN
On July 25, 2026 when starting my vehicle, it began to shake violently and I receive numerous errors, including a check engine light and displays in the infotainment, indicating there were engine and transmission errors with the vehicle. I received a text message notification and in app notification from GMC indicating that there was a critical error and provided error code P0352. This appears to be an error related to a faulty engine, this is the 6.2L V8, which is known to be problematic by GMC. Had this happened while I was driving on the interstate three minutes later, it could’ve resulted in great bodily harm or death to both myself and the general public around me. GMC was later able to reproduce the issue at the dealer, confirming the faulty equipment on the vehicle with less than 16,000 miles on it. The component was replaced by the dealer, however, the vehicle is available for inspection.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758633August 21, 2026
ENGINE
I purchased this truck from a used car dealer. It had received the fix in January this year. They sold it to me I put 15,000.00 down and financed 15,000.00. I had the truck two weeks and was driving down the road to pick up some tools from a friends. I pulled from a drive way I heard a pop likei hit something In The road nothing was in the drive or road I could have hit. I made it two stop signs to make the turn too go pick up the tools and as I am slowing down to stop the stuck shuts off at like 45 miles an hour and leaves me comming to a stop with a truck crank crank crank no start. Cause it said shift I to neutral to restart. I did and the engine went to cranking over and o er really fast. And I was Abel to get control and get stopped at stop sign blocking the stop sign and a guy with a boat behind me. My friend came with his truck and pulled me from intersection up into His yard. And I had car lot I bought it from come get it they tried to finance me a motor thru there prefers dealer. I went to them they explained that the cams and timing chain was staying still as they turned the engine Over by hand. The timing chain stayed staionary. I researched the truck online figured out there is a l87 recall and had it taken to dealer they are offering good will payment on labor because it is 6, 000 miles past the 150000 dead line Wich I only placed just over a thousand of the 156000 miles on this truck. I have been without this truck for 31 days as of today. And I feel they should replace entire engine. I Am so frustrated with this cause I already payed 15000 and don’t have the money to fix this truck.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758649August 21, 2026
ENGINE
engine was replaced by Classic GMC in Katy/Houston, TX in dec 2025 under L87 recall. My wife was driving and was stopped on an off-ramp but still in the traffic lane. It started with a light knock that i thought i heard the day before, but then died on freeway within maybe 15 miles of her driving. Unknown if it knocked louder, but wife says she never heard anything until it died and check engine light came on and engine would not restart. Required tow to GMC dealer. They diagnosed and took 2-3 weeks to source and replace the engine. In july 2026, started hearing very similar noise - this time apparently the water pump seized. Heard noise and got home within about 10 miles. Checked under hood and drive belt was significantly frayed and knocking/metallic noise was intense. Towed to Classic GMC. Not covered under any warranty - my replacement engine did not include a new pump. Cost $1700 at Classic GMC - they said it had no relation to the engine replacement or labor done in December. Unrelated, but icing on the cake - less than 2 hours and 10 miles of picking it up from service, lots of warnings about lane keep, adaptive cruise control, and park sense started going off. Returned to same shop the next day and *poof* the camera and processor that runs all those systems was somehow fried. Unrelated of course. $1200 a but they claimed GM graciously offered to “split the cost with me 50/50” since I just paid so much for the water pump. Picked up from service and traded vehicle in with 2 days.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758664August 21, 2026
ENGINE, FUEL/PROPULSION SYSTEM, POWER TRAIN
I own a 2023 GMC Sierra 1500 Denali Ultimate equipped with the 6.2L L87 V8 engine. The vehicle previously experienced an engine failure that resulted in the complete replacement of the 6.2L engine by an authorized GMC dealership. The replacement engine was installed at approximately 76,316 miles. After approximately 1,000 miles of driving with the replacement engine, at approximately 77,354 miles, the vehicle displayed a check-engine/service warning and experienced abnormal transmission shifting. I returned the vehicle to the GMC dealership for diagnosis. The dealer documented DTC P0747, identified as “Transmission Control Solenoid Valve 1 Stuck On,” and recommended replacement of the transmission control valve body at a quoted cost of $2,665.85 plus tax. The dealership has stated that this transmission condition is unrelated to the recent engine replacement. However, because the condition appeared only approximately 1,000 miles after a complete engine replacement, I have asked General Motors to investigate whether the current failure could be associated with the previous engine failure, the engine replacement procedure, or other related vehicle systems. I have opened a case with General Motors Customer Assistance and have deferred the customer-paid valve-body repair while GM reviews the matter. I am submitting this complaint so NHTSA/ODI has a record that this vehicle experienced a major 6.2L L87 engine failure requiring complete engine replacement and then, approximately 1,000 miles after that replacement, developed a check-engine warning, abnormal transmission operation, DTC P0747, and a condition requiring replacement of the transmission control valve body. I can provide the engine-replacement repair order, current diagnostic documentation, mileage records, dealer repair estimate, and GM case information upon request.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11758123August 20, 2026
ENGINE, POWER TRAIN, VEHICLE SPEED CONTROL
Vehicle: 2026 GMC Sierra 1500 AT4 (3.0L LZ0 Duramax Diesel) Current Mileage: ~16,500 miles Check Engine Light Status: NO Check Engine Light active Description of Incident & Symptoms: •Interstate Incident: While driving at highway speeds, a severe drivetrain vibration occurred (felt like a rear wheel weight flew off). •Dashboard Warnings: Within 5 minutes, intermittent "Traction Control" and "Forward Collision Warning" alerts appeared on the dash, accompanied by a sudden drop in engine power. •Engine Noise & Idle: Once safely pulled over, the engine exhibited a loud mechanical knock and a very rough, unstable idle. •Extended Crank: After shutting the engine off and waiting a few minutes, restarting the truck took roughly twice as long as normal (long crank/delayed start)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0

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