GMC Sierra Complaints (2026)
171 consumer complaints on file.
- #11749941July 13, 2026ENGINE
While driving vehicle the engine lost power and shut off in traffic. There were no warning signs of issues at that time. The dashboard went blank and then reappeared and the truck was in park. after that the truck would not shift gears. The truck was towed to the dealership and found to have had catastrophic engine failure.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11749030July 8, 2026POWER TRAIN, SERVICE BRAKES, HYDRAULIC
The contact owns a 2026 GMC Sierra 3500. The contact stated that while driving at 35-40 MPH on the interstate and towing a loaded trailer, the vehicle experienced reduced braking performance. No warning lights illuminated. The local dealer was contacted and informed that the brakes performed differently. Additionally, the dealer stated that the transmission was not downshifting. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 500.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11749108July 8, 2026STRUCTURE:BODY
My 2026 GMC Sierra has an oil-canned roof from a touchless car wash because the sheet metal lacks structural rigidity. This caused the roof to buckle and caused a permanent fold in the roof of the truck. There is already documented issues for this exact problem on the newer GMC Canyons and Chevrolet Colorado mid-sized trucks. Bulletin for reference NHTSA Official TSB #23-NA-209 PDF. I leased the vehicle on 6/19/2026 and this happened on approximately 7/7/2026. The vehicle only has 1,480 miles on it as of this date.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11748779July 7, 2026ELECTRICAL SYSTEM, BACK OVER PREVENTION: WARNINGS, BACK OVER PREVENTION: REARVIEW SYSTEM BRAKING
No sound at different times. No way to reset issue. TSB issued May 14, 2026 for known issue. As of July 6, no estimate on repair. Blinkers make no sounds, Onstar can call but you cannot hear them. In event of accident, no communication.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11748047July 2, 2026ENGINE
Sudden catastrophic engine failure with only 6000 miles on vehicle on May 26, 2026. 2026 GMC Sierra 1500 AT4X with known defective 6.2L L87 V8. Had to coast across three lanes of traffic to get to other median as highway location was on large curve. Someone very easily could have been hurt or killed.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11747094June 29, 2026BACK OVER PREVENTION: WARNINGS
I bought my 2026 GMC in April. Several times the audio doesn't work work. When this happens audio related safety technology is affected too including turn signal sounds and back camera audio also. A person walking behind the truck can be seen on the screen but no warning beeps are heard. When backing up the warning for getting too close to an object also doesn't work. I called the dealer in early May and was told that this was a known issue and that it needed a software update. took the truck to the dealer on May 8th and the software update was performed. When the update had been completed when I started the truck after the update there was no audio. I told the service advisor it was currently happening and she took it back to the technician. They disconnected the battery cables to reset the system and told me to do that in the future until the issue is resolved. I opened Case #100978480 with GM on June 1st because I wanted to be sure that GM was also informed of the issue. I was hoping they would be proactive and report back to me what they were doing to resolve this issue. Instead I was told that I need to call the dealer and the dealer would call GM because an update might be available but dealers wouldn't be informed and wouldn't check unless I called.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746991June 28, 2026ENGINE
My motor has a catastrophic failure. Started sputtering and Squealing.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11746601June 26, 2026WHEELS, SUSPENSION, STEERING
In early June 2026 I discovered a sheared pin on the front control arm of my 2026 GMC Sierra 1500 AT4X (VIN [XXX]), sold to me new by Parks GMC, Kernersville NC, with a dealer-installed Performance Package modifying the factory suspension. I delivered the truck to Parks GMC for warranty repair. The dealer represented it as a 1-2 day job. The truck was out of service approximately 2 weeks. The dealer sub-contracted the work to a third-party shop (CCV). At pickup, the dealer provided written documentation stating the repair was NOT PERFORMED. Neither the dealer nor I has been able to obtain any documentation from CCV describing what, if anything, was actually done to the vehicle. THREE UNRESOLVED SAFETY CONDITIONS: SHEARED FRONT CONTROL ARM PIN — original failure, status of repair unknown and undocumented. TIRE-TO-BODYWORK CONTACT — front tires intermittently rub the inside of the wheel wells during normal driving and steering, causing visible damage to the plastic mud guards. Tire-to-bodywork contact creates risk of sidewall failure, sudden air loss, and loss of vehicle control. FRONT RIGHT SUSPENSION CREAK — loud, persistent creak from the front right suspension during low-speed driving and steering inputs. Present at service drop-off, never addressed. Consistent with a worn, loose, or improperly installed suspension component. I escalated to Parks GMC management and GMC Customer Assistance. Parks has not provided a written repair plan, no decision-maker has contacted me, and the only response has been "looking into it." GMC Customer Assistance declined to assign a District Service Manager. I am filing to document these suspension and tire safety conditions in the federal database against this VIN and to request NHTSA evaluation of whether further action is warranted. 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
- #11746541June 25, 2026ENGINE
2026 GMC Sierra 1500 AT4X with 3898 miles. Driving 71mph on state highway on flat grade road. Lost power and vehicle shut down after pulling off the road. No previous lights or warning signs prior to power loss. Vehicle would not start afterwards. OnStar Diagnostics sent ECM Engine and Transmission System code P0016. Had vehicle towed 100miles to GM dealership. Upon inspection of vehicle, the Service Department contacted me the following day and said the the vehicle needed an entire engine replacement according to GM cooperate. I asked if it had anything to do with the 6.2L V8 L87 engine problems from previous recall years of 2021-2024. Service tech stated yes it was more than likely the same issue. Very unhappy with my new GM vehicle purchase. Will have to have a full engine replacement BEFORE my first oil change!
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11744605June 16, 2026ELECTRICAL SYSTEM, FUEL/PROPULSION SYSTEM, POWER TRAIN
Have been driving it on four separate occasions and the engine will start running rough and shut off leaving me with no power brakes or power steering. Once when I was going about 30 miles an hour the other three times when I was coming to a stop with a trailer on just took it in Kendall Chevrolet for the first time they are still working on it but unable to duplicate the problem this is a very serious safety concern for myself and possibly for others that have the same issue
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11744121June 15, 2026ENGINE
I was driving on interstate 95 at approximately 70 to 75 mph when I lost all power and compromise steering with tractor trailer behind me God willing I was able to pull over to the shoulder. My safety was compromised and I lost all faith in Gmc. My vehicle has been out of service for 27 days at this point while waiting for an engine replacement with no ETA on service. According to Pennsylvania lemon law after 30 days a lemon law claim can be submitted
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11743279June 10, 2026ENGINE
The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, there was an abnormally loud and rough knocking sound coming from the engine block. The oil pressure decreased to zero, and the engine seized. There was no warning light illuminated before or after the failure. The vehicle was towed to a dealer, where it was diagnosed with a blown engine. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 5,018.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11742302June 5, 2026ENGINE
Total engine failure on 5/31/26. Truck lost engine power while on highway and had to be towed to dealership where they found the lower end of the engine failed. Engine and radiator replacement needed, both are backordered with no eta.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11742370June 5, 2026ENGINE
I bought a brand new 2026 1500 GMC sierra AT4X and after 1,800 miles the engine seized and failed.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11741215June 1, 2026ENGINE
While driving approximately 45 MPH, I slowed to make a right turn into a parking lot. The engine suddenly stalled and lost all propulsion. The vehicle retained electrical power but automatically shifted into NEUTRAL, and would not shift back into DRIVE. I braked to a stop, temporarily stranding the vehicle and blocking traffic in the parking area. Attempting to turn the vehicle off via the START/STOP button actually restarted the engine, confirming the stall. The truck then shifted into DRIVE and operated normally. A subsequent OnStar diagnostic scan found no active trouble codes.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11741251June 1, 2026ENGINE
Heard clanging noise under hood as I was driving and truck just stopped. Tried to restart and nothing! Towed to dealership where they found the engine has to be replaced.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11740285May 27, 2026FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL
Traveling home the day I purchased vehicle going through [XXX] with cruise set on 35,negotiating a right handed curve in the road and a vehicle was stopped in center lane turning left and my vehicle abruptly braked causing the vehicles behind me to take evasive action to keep from hitting me from behind 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
- #11740289May 27, 2026ENGINE, STEERING, POWER TRAIN
While driving on the highway, the steering became much more stiff, and then I heard metallic clanging sounds for a few seconds. The dashboard said press start to start Vehicle. I pressed start while going 30 miles an hour and all lights and instrument clusters went black. I pulled into the grass median where the truck would not start or shift gears. Truck was towed to a GMC dealership
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11740229May 26, 2026TIRES, TIRES:SIDEWALL
DOT AH9K82 3425 LT265/70R17 121/118Q All four brand new tires on my brand new truck have bulges on the sides of the tires. The truck feels floaty and unsafe at highway speeds. The car dealership is saying it’s fine, won’t replace them, and says it’s a known issue with the tire.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11739028May 20, 2026ENGINE
The contact owns a 2026 GMC SIERRA 1500. The contact stated while driving 40 MPH, the vehicle independently engaged into limp mode. A dealer was contacted. The vehicle was towed to the dealer where it was diagnosed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not notified on the failure. The approximate failure mileage was 10,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0