GMC Sierra Complaints
15,732 consumer complaints on file.
- #11723729March 11, 2026FUEL/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
- #11723734March 11, 2026SERVICE BRAKES
I was out one day for lunch and my brakes stopped working on my truck. I had the truck towed after I limped home in it. The master cylinder failed at 4,200 miles causing the brakes to fail. It was replaced by the dealership.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723197March 10, 2026POWER TRAIN
While driving down a highway doing between 45 and 55 mph the transmission suddenly and completely faulted causing the truck to come to a complete stop. Just enough power to get to the shoulder luckily. The transmission had basically completely blown out, fluid everywhere. The insurance company did not find any comprehensive damage. The entire transmission needs to be replaced. There were no indicators showing any problems, no alerts, no warning whatsoever. Mechanics said there was a lot of metal coming out of the transmission. The truck is currently in a mechanic shop awaiting the new transmission, so at this time it is available for inspection. The safety issue here is that it happened on a busy highway, and the vehicle was no longer drivable so it needed to be towed causing more time spent on the side of the road.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723247March 10, 2026POWER TRAIN, ENGINE
[XXX] and [XXX] of 2025 the 6.2 V8 engine died while driving down the highway in Houston. The truck was bought brand new in January of 2025 with 100 miles on the odometer. The first engine failure happened [XXX] with 10,350 miles. Replaced, the second failure happened [XXX] with just under 25,278k miles. Once again the engine was replaced and took almost 6 weeks. 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
- #11723255March 10, 2026ELECTRICAL SYSTEM, ENGINE
Following the remedy of the engine recall in 2025, the truck started having intermittent electrical issues (i.e. warning lights on dash turn on/off: service 4WD, Loss traction Control, etc) come one while the truck is being driven. If the truck is turned off while the dash warning lights are on, it will NOT Start for about 24 hours. If the warning lights are ignored, eventually they will go off on their own. Additionally, the truck is having "no-start" problems (randomly the truck does not start, then after a few days it starts). A New development, when backing up there is a scraping/squealing sound (possibly universal joint). Truck has been back to the dealership that replaced the engine block for the recall and they have failed to identify any issues as these problems are intermittent. Engine Recall Replacement Invoice (Attached)
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723265March 10, 2026SERVICE 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, 2026ELECTRICAL 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
- #11723389March 10, 2026ENGINE, STRUCTURE:BODY
The motor stoped working 6.2. Left me stranded in the middle of the road. No warning, the engine just gave up and stopped working. As well as the grill flying away and breaking my windshield, this happened last year in february while driving 75 mph.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723417March 10, 2026POWER 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
- #11723049March 9, 2026ELECTRICAL SYSTEM
Tailgate opens randomly on numerous occasions. Sometimes it won't open after pressing the button.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723067March 9, 2026ENGINE
While driving, my vehicle experienced a sudden and complete engine failure without any prior warning. There were no warning lights, dashboard alerts, or performance issues that would have indicated an impending mechanical problem. The failure occurred unexpectedly while I was actively driving on a public roadway. After the incident, the vehicle was inspected and diagnosed by a licensed mechanic. The diagnosis determined that an internal engine lifter failed, which subsequently caused damage to the camshaft. This type of failure appears to be the result of an internal mechanical defect rather than any form of neglect or improper maintenance. The abrupt nature of this engine failure created a serious safety hazard. The vehicle suddenly lost the ability to operate normally, forcing me to slow down and stop in active traffic. This unexpected loss of power placed my safety, as well as the safety of other motorists on the road, at significant risk. A critical engine component failing without warning while the vehicle is in operation raises serious concerns about reliability and safety. The vehicle has been properly maintained throughout ownership. All routine maintenance and servicing have been performed by licensed mechanics, and I can provide complete maintenance records documenting this history. At no point prior to this incident were there any signs, warnings, or diagnostic alerts indicating an issue with the engine. The vehicle has already been fully inspected and diagnosed by a licensed mechanic, and the findings are available for review. If necessary, arrangements can be made for the manufacturer or an authorized representative to inspect the vehicle and verify the damage. Given the sudden nature of this failure, the internal engine damage involved, and the safety risk it created while driving, I am requesting that this issue be formally reviewed and addressed by the manufacturer.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723074March 9, 2026POWER TRAIN:AUTOMATIC TRANSMISSION
The contact owns a 2017 GMC Sierra Denali. The contact stated that while driving on the highway at an undisclosed speed, the vehicle jerked, failed to accelerate, and stalled. The vehicle was unable to shift into third gear. The check engine warning light was illuminated. The vehicle was drivable and was taken to the dealer. The vehicle was diagnosed with a wiring harness failure on the transmission. The vehicle was repaired based on the diagnostic test but failed to fix the vehicle. The vehicle was parked at the residence and was undrivable. The failure mileage was approximately 103,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723154March 9, 2026ENGINE
Took it to dealer for engine sound said nothing was wrong 4 days later rod bearing went out while driving. Truck no longer able to drive
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11723178March 9, 2026ENGINE, LANE DEPARTURE: BLIND SPOT DETECTION
The 2019 GMC Sierra AT4 with the 6.2L V8 engine began making a rattling or tapping noise at 45 mph. No warning lights appeared on the dashboard. When starting the engine and idling, a similar noise can be heard from the engine. I bought the vehicle used from a dealership one month ago, with 80,000 miles, and the second issue is the complete failure of the blind spot warning system on both mirrors. It was a one-owner vehicle with a clean Carfax. I am scheduled to take the vehicle to the dealership's service department for a full inspection.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11722893March 9, 2026ENGINE
Engine oil pump solenoid. Diagnostic code P06DD.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11722758March 8, 2026ENGINE
Another GM truck AFM failing. It failed at 70,000 miles causing P0307 cylinder 7 misfire. No aggressive driving just commuting to work. Truck just got done with a new oil change. It's another to add to the hundreds/thousands seen on Reddit threads of all 5.3/6.2 AFM/DFM that this organization turns a blind eye to.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11722763March 8, 2026STRUCTURE:BODY
I was driving down the road and my top grille molding flew off
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11722798March 8, 2026ELECTRICAL SYSTEM, UNKNOWN OR OTHER, EXTERIOR LIGHTING
Randomly when the truck is turned on, the turn signals will stop working, no noise, nothing. When this happens, the infotainment system also stops working. It is unsafe to be driving and not knowing if your signals are working or not. This has been happening since the truck was purchased from the dealer.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11722805March 8, 2026ENGINE, UNKNOWN OR OTHER
[XXX] we bought our 2021GMC Sierra 1500 from Dealer with 39842 on it. we drove the truck 2910 miles when we checked the oil it was 2 quarts low at 42752. we added oil at that time and called our local dealer to make appointment . appointment at Bowser route 51 Pleasant Hills PA 15236 They informed us they would have to charge us for an oil change to start an oil consumption test on 10/23/25 miles 43829. 11/24/25 brought back to Dealer they said the oil was full yet i checked it in morning it was1/4 low. 1/7/26 brought back to dealer this time they let our truck sit over night the best way to check it and found it to be 3/4 low with only 1,698 miles driven also the antifreeze reservoir was low also they topped off both. 3/8/26 I Checked it ,its now 1 quart low with 1,097 miles driven milage on truck now is 46,623. Summarize GMC will not even look into why my truck is using oil not once my truck is still under warranty where is the consumer protection. 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
- #11722817March 8, 2026POWER TRAIN, ENGINE
Driving down the road and engine shut off and would not start back. Had it towed to dealer and it needed a motor replacement. Waited over a month for the shop to finish it. New motor has 3k miles on it and is making noise, transmission is stuttering hard and the air conditioning quit working all around the same time. Had to take the truck back to the dealer after the replacement motor was installed because of a faulty “new” starter.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0