GMC Sierra Complaints
15,732 consumer complaints on file.
- #11745896June 23, 2026POWER TRAIN
The contact owns a 2020 GMC Sierra 1500. The contact stated that upon taking the vehicle to the dealer for a transmission fluid flush and refill, the contact was informed that the transmission was inoperable, and the vehicle could not be driven to the residence. The dealer determined that the torque converter needed to be replaced. The dealer replaced the torque converter and advised the contact to drive over 1,000 miles for the issue to self-correct. The contact stated that the vehicle continued to shudder and drive bumpy while driving after 1,000 miles. The vehicle was taken back to the dealer, where the torque converter was replaced a second time; however, the failure persisted. The dealer informed the contact that the diagnostic test results were sent to the warranty company for the transmission replacement approval. The vehicle was not yet repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 85,165.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745942June 23, 2026ENGINE
While driving, the vehicle experienced a sudden and momentary loss of power, similar to briefly applying the brakes, after which power resumed. This was followed by a progressively louder squealing noise. I pulled over to investigate, at which point the engine shut off and a low oil pressure warning appeared on the dashboard. The vehicle would not restart. The vehicle was then towed to a dealership, where initial inspection suggested the issue may be related to the L87 recall involving the crankshaft bearing.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745943June 23, 2026POWER TRAIN
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed, but the vehicle continued to move forward. There was no warning light illuminated. The vehicle was taken to the dealer and was diagnosed with transmission failure. The contact stated that the valve body and torque converter needed to be replaced. The dealer informed the contact that the transmission might need to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 65,561. The VIN was unavailable.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745944June 23, 2026UNKNOWN OR OTHER
This vehicles top portion of grill trim is starting to come loose, as this is a safety concern while on the highway, I had another vehicle that the trim flew off completely, (same year and model) while i was on the highway. This could hit another vehicle if this happens, or god forbid a person who happens to be on a sidewalk. I looked into this and found that there is a recall for the same issue on 2022 models that has not been extended to the 2024 model (Recall N242490120). This recall should be extended to the 2024 models as this is a huge safety concern.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745947June 23, 2026UNKNOWN OR OTHER
Upon driving on the highway, I was doing about 73mph, something back flew up and smacked the windshield then the car behind me ran over that piece. After stopping and looking I realized the top trim to the grill flew off. There is no recall for this even though this is a safety concern. If I was near a sidewalk to a motorcycle behind me this could have injured someone severely. Upon research I found that there is a recall for the 2022 model for the same problem (Recall N242490120), this needs to be extended tot he 2024 model as I have another truck (same year and model) that is showing signs of the same issue. This is a huge safety concern.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745952June 23, 2026ENGINE
The AFM caused piston flapping and other major engine problems such as abnormal wear. The problem with the engine could have caused a catastrophic failure along the side of a highway. The problem has been diagnosed and the engine has been replaced at my expense. The repairs were made at a local mechanic shop. The engine would start make a loud ticking noise at 2000 RPM or above. The mechanic shop referred to this as piston flapping. This was caused by inadequate oil pressure at all cylinders due to the Active Fuel Management.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746005June 23, 2026EXTERIOR LIGHTING, ENGINE, ELECTRICAL SYSTEM
I am retired and have always bought GM vehicles which are taken care of with required oil changes etc. This one I have only owned 25,000 mi each year (I have owned two years). So, when purchased it has high 50,000 miles not sure of exact, and it has only been driven 2 years. When calling escalation at GM, they act as though it doesn't matter and too bad. 110,000 miles and the truck needs a new motor. This is what we are told and 10,000 more than the initial 1500 to tear it down. This truck is not broken due to us, this is a problem with the manufacturer and the responsibility needs to be addressed. My husband has a heart issue and he almost didn't make it home. I'm not accepting that nothing be done, since next we need a lawyer and a media appointment. This isn't right when you see thousands of people with the same GMC Sierra trucks online with complaints of the same valve and motor issues. This needs completely replaced and not by a customer, by the manufacturer. How can 1500 people new wrong on one sight stating the same as we have had. This person who is responsble for reporting and making sure we are safe needs to be fired. I am writing my representatives, senators etc to let them know this is going on. No one should pay for the mistakes of bad engineering. PERIOD.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746044June 23, 2026UNKNOWN OR OTHER
I was driving down I-25 interstate and the sunroof exploded outward on the vehicle and sounded like i shot gun going off in the vehicle. I did experience a hard breaking situation due to the loud noise, no traffic accident from this situation. Called GMC service and warranty department and glass is only covered for 1 year.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746054June 23, 2026ENGINE
No warning lights, engine stalled in the middle of the freeway almost got killed by a semi truck was behind me, engine lost power and found that needed new engine because of the camshaft and internal damage.confirmed by certified mechanic
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746087June 23, 2026ENGINE
Loud knocking noise started while motor is running. Took to dealer who confirmed the noise and inspected. Metal confirmed in the oil pan and throughout motor. Service advisor said a new motor will be needed and has sent info to GM. This vehicle was checked per the recall and passed the pico test. Oil was changed to new GM 0-40 by dealer.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745600June 22, 2026STRUCTURE:BODY
The attachment points for the upper chrome grille deflector have fractured, causing the trim piece to detach completely while driving and fly over my windshield which startled me and made me swerve dangerously. This is a known recall for the truck year before me and should clearly affect my truck too since the same description happens here
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745703June 22, 2026ENGINE AND ENGINE COOLING
The contact owns a 2021 GMC Sierra. The contact stated that while driving at approximately 40-45, the engine warning light illuminated. There was an abnormal sound coming from the fan. The vehicle was taken to the local dealer, where it was diagnosed and determined that the coolant flow valve needed to be replaced. The vehicle was not included in a special coverage program. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 50,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745786June 22, 2026STRUCTURE:BODY
The front grill deflector sheared off of the truck when driving in the highway. The highway speed was 65 mph and the deflector flew out in to traffic. There was no warning or symptom prior to the problem or failure. This is a common ongoing issue with the same make/model of the previous year 2022 with an actual open recall unfortunately.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745543June 22, 2026ENGINE AND ENGINE COOLING
The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving 75 MPH, the message "Engine Power Reduced" was displayed and the vehicle decelerated and stalled. The vehicle was pulled over onto the shoulder and failed to restart. Roadside Assistance was called to the scene, and the vehicle was towed to the local service center, diagnosed, and it was determined that the engine Cam Actuator screws had failed causing metal shavings to enter the engine and turbo. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer and local dealer were notified of the failure. The failure mileage was 95,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745550June 22, 2026SUSPENSION
The contact owns a 2022 GMC Sierra 3500. The contact stated that while driving at slow speeds, there was a loud banging sound coming from the vehicle. The contact exited the vehicle and became aware that the front passenger’s side tire was inverted towards the engine compartment. Pictures of the damages were taken to a dealer, and the contact was informed that the control arm had snapped; however, the vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was 10,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11745455June 21, 2026POWER TRAIN, ENGINE
[XXX] [XXX] Phone: [XXX] Vehicle Information: Year: 2023 Make: GMC Model: Sierra Denali Ultimate Engine: 6.2L V8 VIN: [XXX]: Mileage: Approximately 52,000 miles BACKGROUND: I previously had the engine serviced under a GM recall campaign related to known 6.2L V8 engine concerns. Despite that repair, the vehicle has since experienced two separate highway-speed loss-of-propulsion events. COMPLAINT The vehicle suddenly lost power while being driven at highway speed. No warning lights, check-engine lights, reduced-engine-power messages, or transmission warnings appeared. In both incidents, I was forced to coast to the shoulder of the roadway. The vehicle would not resume normal operation until it was stopped and restarted. This condition has now occurred twice. SAFETY CONCERN The sudden loss of propulsion during highway operation creates an immediate safety hazard and increases the risk of collision due to the inability to maintain speed with surrounding traffic. REQUESTED NHTSA ACTION 1. Record this complaint as a repeat loss-of-propulsion event. 2. Evaluate whether similar complaints exist involving 2023 GMC Sierra Denali Ultimate vehicles equipped with the 6.2L V8. 3. Consider this complaint in any current or future investigations involving loss of propulsion, stalling, engine failure, or powertrain concerns. 4. Review whether vehicles previously repaired under GM recall campaigns continue to experience similar failures. [XXX]: Update – Vehicle Disabled and Awaiting Engine Replacement Since filing my initial concerns regarding repeated loss-of-propulsion events, the condition of my vehicle has significantly worsened. During the dealership's inspection and test drive, the engine reportedly failed and locked up. The vehicle could not be restarted and required further diagnostics. On June 20, 2026, I received a text message from the dealership that the required engine parts remain on backorder 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
- #11745287June 19, 2026TIRES
275/65R20 - Goodyear Wrangler. This is the tire that came with the vehicle. It had approximately 32,000 miles. The tire separated and exploded. We installed the spare but one of the other tires is getting ready to explode. This is not normal wear and tear. This is out of the ordinary that tires on a new vehicle explode. We were on [XXX] when this happened. This tire is a death trap. This is forcing us to replace all 4 tires because we do not know what is going to happen. The dealership (Jerry Seiner) will do NOTHING. 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
- #11745292June 19, 2026ENGINE
• While driving a loud popping and clicking noise started coming from the engine and the truck started shaking. The vehicle is available for inspection • It was a busy two lane road and I had to continue about 30mph under the speed limit to safely get off the roadway • upon start up the engine clicks and pops with rough idle and the truck shakes. A mechanic looked at it and stated it sounds like a lower rod bearing noise • No further inspections have been done • A Service ESC warning popped up when the engine started making noise during the incident. The truck had been taken in twice for rough idle and engine noises prior to 100k miles, but the dealership stated that the noise and feel was normal for the 6.2L engines
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11744918June 18, 2026ENGINE, FUEL/PROPULSION SYSTEM
1. The L87 Engine Loss of Propulsion failed and is available for inspection at the service department at Power Swain Chevrolet dealership, Fayetteville, NC. 2. I, other vehicles, cyclists, and pedestrians were at risk. That vehicle could have come down on the highway, causing a vehicle pileup, which could have caused mass casualties. 3. The problem is known; the service advisor informed me the vehicle's engine needed to be replaced. 4. There were absolutely zero warning lamps or My GMC app alerts to announce vehicle issues. I have attached the last two maintenance records I have on hand. I suspect the dealership will try to deny responsibility for repairs. An extended warranty most nearly means we expect it to break down and your safety is not our concern.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11744937June 18, 2026SERVICE BRAKES, STEERING
Normal driving 40mph brake failure and power steering loss. Towed vehicle to dealership
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0