GMC Sierra Complaints (2026)
171 consumer complaints on file.
- #11725387March 18, 2026ELECTRICAL SYSTEM, UNKNOWN OR OTHER, STEERING
I had this truck as brand new for approximately 24 hours when it had a major failure. It had 450 miles on it at time of purchase, but was sold as new. While driving at 45MPH it had a check engine light, service power steering message, lost power steering, lane departure system failure, and reduced power amongst several other lights on the dash. I limped the truck into a gas station parking lot. After turning the truck off, it would not restart. I unhooked the battery for a minute and hooked it back up. The truck did restart with no messages or check engine light. I was able to safely get it to the dealership. As a result of this issue, I forced the dealership to cancel the trade.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11724264March 14, 2026ENGINE, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING
I am the owner of a 2026 GMC Sierra 1500 Denali Ultimate equipped with the 6.2L V8 L87 engine (VIN: [XXX] ), purchased new approximately three months ago. I am filing this complaint proactively. I have experienced no engine failure or symptoms to date. However, I am filing based on a documented pattern of L87 engine failures in 2025 and 2026 production vehicles, confirmed by multiple GM dealership technicians, which suggests that the manufacturing defect underlying NHTSA Recall 25V-274 may not have been fully resolved by GM’s stated production improvements dated June 1, 2024. NHTSA Recall 25V-274 (April 2025) covered 597,630 vehicles from model years 2021–2024 for catastrophic L87 engine seizure caused by connecting rod bearing failure and crankshaft defects. GM excluded 2025 and 2026 model year vehicles based on a claimed manufacturing fix. However, multiple 2026 production vehicles have since experienced the same bearing failure at extremely low mileage. Open NHTSA Investigation EA25007 is already examining vehicles outside the original recall window, and Recall Query RQ26001 is investigating the adequacy of GM’s remedy. I am requesting that NHTSA consider expanding the investigation scope to include 2025 and 2026 model year vehicles. As a 2026 owner of a $90,000+ truck with the identical engine configuration, I believe my vehicle warrants inclusion in any expanded investigation or recall action. 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
- #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
- #11721299March 1, 2026POWER TRAIN, VEHICLE SPEED CONTROL, ENGINE
My engine seized up on me on the highway. I was stranded and couldn’t start the vehicle and it was freezing outside.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11721108February 28, 2026ENGINE
I was out of town and driving on the highway around 75 MPH, when the motor suddenly lost all power. I was driving in the far left lane approaching an overpass. The sudden loss made it next to impossible to make it off the overpass on a very busy freeway safely while trying to navigate many cars trying to pass me . The truck came to a complete halt on the white shoulder line, 50' off of overpass SH 31. The truck would not restart or do anything i could not push it any further off road. I excited the e truck and stood off the freeway for my safety, as the truck was on very edge of freeway. GMC Roadside assistance took my truck to nearest dealer. This occurred on a Friday, dealership gave me a loaner car to get home as i was from out of town. They stated it would probably be the following Tuesday maybe Wednesday before they could tell me anything. I never heard from dealership service department, so i called them on Thursday morning and was told my truck motor had seized up and a new motor was needed. Service advisor stated GMC had been contacted and paper work started and I would be getting a new motor. The service advisor also stated that he had called and left a message. We verified my phone number and he had correct number, however I still never receive a call or voice mail. I still have not received any documentation on the failure or a repairs needed.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11720900February 27, 2026ENGINE, STEERING
I stopped at a red light in the middle of a 50 mph intersection when the light turned green The engine completely shut off, and it didn’t want to turn back on. I was stuck in the middle of the intersection in a very high risk area, putting myself and other drivers at risk. OnStar diagnostics didn’t report any issues with the truck. According to their diagnostics, everything should have been running perfectly fine. The motor shut down completely and we weren’t able to shift the truck into neutral in order to try to move out of harms way. There was no warning lights or anything before this happened. The first tow truck driver that came by was told that he was there “in order to do a jumpstart” He ran a diagnostic on both of the batteries and said that they were perfectly fine. Another tow truck had to be dispatched since the first wasn’t equipped to take the truck. In total we were stuck in the middle of the intersection for almost three hours. The amount of times we almost had someone crash into us during that time was very concerning. Dashboard and lights were all working perfectly fine. Auto start stop technology seems to have shut down the motor and was not able to get it to turn back on . This vehicle is a safety hazard.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11720377February 25, 2026EQUIPMENT
The contact owns a 2026 GMC Sierra 1500. The contact stated that after purchasing the vehicle, there was no Owner’s Manual in the vehicle. The contact inquired about the Owner’s Manual and was informed by the dealer that an Owner’s Manual was no longer printed. The contact checked online and became aware of FMVSS 225, which was related to the Owner’s Manuals for similar vehicles. The contact researched NHTSA Campaign Number: 25V815000 (Equipment), addressing the lack of an Owner’s Manual for 2026 Chevrolet Silverado 1500, 2500, and 3500 vehicles. The manufacturer was not notified of the issue.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11719813February 23, 2026ENGINE, FUEL/PROPULSION SYSTEM
"Vehicle is experiencing symptoms consistent with the 6.2L L87 engine bearing failure investigation (NHTSA Probe January 2026). Despite two repair attempts, the dealer claims 'operating as designed.' I have experienced persistent engine stumble,hesitation, erratic tachometer needle flutter and significant vibrations felt through the floorboard and seats during operation. These defects substantially impair the use ,value and safety of my vehicle.This is a serious safety concern as it creates a risk of catastrophic engine seizure at highway speeds. Manufacturer has been sent a formal 'Last Chance' letter under NJ Lemon Law." Reference # 1771884
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11719035February 19, 2026ENGINE, ELECTRICAL SYSTEM, POWER TRAIN
Vehicle stalled in busy intersection in McKinney Texas , unable to start are shift into a neutral position on transmission to remove from extreme dangerous intersection, sheriff advised that road side assistance that was contacted is not going to be in time (90min)to keep from causing an ongoing traffic backup , sheriff dispatched their own towing service to resolve the situation from getting extremely dangerous .vehicle and my wife was towed to McKinney Buick gmc dealership.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11718072February 15, 2026POWER TRAIN, ENGINE
Odd noise from bell housing area at 1200 miles that went with engine rpm. Took the truck in to the dealer and they said they couldn't recreate it but to bring it back in if it returned. Jan 27th at 5200 miles on the truck, I was driving down the highway at 60mph and got a reduced acceleration message on the dash along with a check engine light. Brought it to the dealer and was informed it was a bad thrust bearing and needed and engine and turbo replacement. Still waiting for the truck to be done.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11717546February 12, 2026POWER TRAIN
My 2026 GMC AT4 3.0L Duramax had a catastrophic engine failure on Sunday, February 8, 2026. It went into reduced acceleration and also fault code PO6DD. Thankfully I was not on a highway. The truck would not run over 45 MPH on flat ground, and then by the time I got it to a safe location 5 miles away it would not run over about 30MPH. This obviously resulted in the truck being towed to a dealership. I have been told the entire engine will be replaced. Upon further reading, I suspect this is a thrust bearing failure that is a well-known issue in this LZ0 Duramax engine. What I have read, this issue is occurring mostly on trucks built from May-Sept 2025, and my truck has a 7/2025 build date. This could have been major safety hazard if the engine had failed in a major freeway/highway.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11717655February 12, 2026POWER TRAIN
I am submitting this complaint regarding a recurring transmission issue in my vehicle. The transmission consistently jerks and shifts erratically, particularly in the morning during initial operation when at cruising speeds of about 50-75 mph. This behavior occurs when the transmission temperature is below approximately 100°F and happens on a daily basis. The gear changes feel harsh and abrupt, kind of like it doesn’t know what gear to be in its raising concerns about both drivability and long-term transmission reliability. I brought the vehicle to an authorized dealership for inspection. After evaluating the issue, the dealer informed me that the behavior was due to the vehicle being in “Sport Mode.” However, this explanation does not resolve the concern, as the severity and consistency of the jerking appear abnormal and occur regularly under the same temperature conditions. Given the persistent nature of this problem and its potential safety implications — especially during acceleration and low-speed driving — I am requesting that this issue be formally documented and investigated. Thank you for your attention to this matter.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11716711February 9, 2026ENGINE
The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle made an abnormal sound and failed to accelerate as needed. There was no warning light illuminated. The vehicle was taken to the dealer, who determined that the engine needed to be replaced. The vehicle was not repaired and remained with the dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 6,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11715890February 5, 2026ENGINE
"Vehicle exhibits a severe RPM flutter and rhythmic harmonic vibration at idle. These symptoms are consistent with manufacturing defects in the connecting rod and crankshaft currently under NHTSA RQ26001 and EA25-007 investigations for the GM 6.2L L87 engine. The defect presents a substantial risk of sudden engine seizure and loss of propulsion while driving. Vehicle is currently out of service at Jim Curley GMC for its first repair attempt. The dealer has stated repairs will not begin for several days."
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11713545January 27, 2026ENGINE
Total engine failure at highway speed with loss of propulsion . Catastrophic engine loss with 3,000 miles . GMC never fixed the problem with the 6.2 l87 like they said
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712904January 23, 2026FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL, LANE DEPARTURE: ASSIST
GMC SUPER CRUISE MALFUNCTION NO WARNING BEFORE SUPERCRUISE SHUTS OFF PASSING A CAR ON FOUR LANE HIGHWAY (SUPER CRUISE ENABLED) SUPER CRUISE SHUT OFF AND TRUCK CONTINUED HEADING FOR THE CENTER GAURD RAIL.(I CAUGHT IT BEFORE IT BECAME AN INCIDENT). SUPER CRUISE ABRUPTLY SHUTS OFF (NO WARNING) AND WITHIN A COUPLE THOUSAND FEET IT TURNS ON. MY FIRST TIME USING SUPERCRUISE AZ HIGHWAY 87 N BOUND JUST BEFORE RYE AND AZ HIGHWAY 260 BETWEEN PAYSON AND CHRISTOPHER CREEK I CALLED MY DEALERSHIP BUT IT WAS LIKE UH HUH OK I'LL LET GM KNOW.- NO SUPPORT! THE ONLY INDICATOR IS ON THE STEERING WHEEL A RED,GREEN OR YELLOW LIGHT.RED IS OFF-GREEN IS ACTIVE, AND YELLOW LIGHT NO SERVICE. RED LIGHT COMES ON AND SEAT VIBRATES SUPERCRUISE DROPS OUT.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712965January 23, 2026ENGINE, POWER TRAIN
I heard a loud metallic knock that was not consistent with normal engine noise. I noticed the oil pressure was on the lower end of the scale but not abnormal based on how it is displayed. I decided to take the vehicle to the dealer ASAP for an oil change (that was coming due) and discuss with them. I drove roughly 20 miles from start of noise until delivery at the dealer. The truck gave me a "Reduced Acceleration, drive with caution" message 10 miles prior to the dealership but no associated lights, engine codes, check engine light or associated alerts on the myGMC app. Dealership found oil pressure ranging between 4-8 psi, and a failed oil pressure control solenoid, heavy metal debris in the oil pan including parts of the thrust bearing and oil squirter. Entire engine and turbo replacement was required. Truck had 143 hours on the engine and 6,300 miles. It was produced in August of 2025 with a purchase date of 17 October 2025. Produced: 8/25 Purchased: 10/17/25 Failed: 12/30/2025 Returned with new Engine: 1/23/26
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11712398January 21, 2026ENGINE, FUEL/PROPULSION SYSTEM, POWER TRAIN
2026 GMC Sierra Elevation X31 with 3.0 Duramax Diesel engine, 132-miles, thrust bearing 1.53-mm out of tolerance requiring engine and turbo replacement. Engine build date 25219 (07 AUG 2025), vehicle assembly date August 2025, purchased 10 OCT 2025, entered service for engine and turbo failure on 11 NOV 2025, returned 10 JAN 2026.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11711666January 17, 2026SEATS
Metal/chrome decal on seat pulls hair frequently, making sitting back in a safe position uncomfortable. Fix this issue.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11711300January 15, 2026POWER TRAIN
26’ GMC Sierra 1500 AT4 3.0l Duramax experiencing Harsh shifting occurring sporadically while accelerating and deceleration. More frequent and severe during quick deceleration. Severe clunking/rear wheel lock up while reversing. Very repeatable. Truck was a dealer demo and had 2400 miles on it when I bought it last week. Took it in to the dealer today and they said I need a complete new transmission.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0