Complaint volume
45 consumer-submitted complaints are matched to this model year. Treat the count as a research signal, then read the actual summaries for repeated symptoms.
Complaint records
2026 GMC Sierra Complaints
45 consumer-submitted complaints on record for the 2026 GMC Sierra, grouped by component category.
45 Total complaints
0 Crash reports
0 Fire reports
0 Injury reports
Complaint data reflects consumer-submitted reports. A complaint is not proof
of a defect, recall, or manufacturer fault. Enriched severity fields come
from official bulk records when the complaint can be matched by ODI number.
Buyer interpretation
How to use these complaints before buying
Complaint records are most useful when they turn into inspection points, seller questions, and comparison checks against nearby model years.
Pattern to inspect
The most common categories are engine, power train, power train,engine. Use those categories as a test-drive checklist instead of judging the vehicle from the total count alone.
Severity context
The enriched records we matched do not show crash, fire, injury, or fatality flags. Still check complaint summaries for repeated drivability, braking, electrical, or visibility symptoms.
Mileage clue
Mileage is available on 2 complaints, with an average reported failure mileage of 3,150 miles. Compare that with the mileage on the listing.
Questions to ask the seller
- Have you had any problems related to engine, power train, power train,engine?
- Can I see recent maintenance and repair records?
- Has the vehicle ever been towed, involved in a crash, or repaired for the same issue twice?
- Can we also check the recall record for this 2026 GMC Sierra?
Used-car checklist
Use these complaints before the test drive.
Build a buyer checklist to turn these issues into questions and inspection points.
2026 GMC Sierra
Build buyer checklist Compare with other years Sends year, make, and model to pre-fill your checklist.
How severe are the 2026 GMC Sierra complaints?
0 Crash
0 Fire
0 Injury
0 Fatality
0 Towed
0 Medical attention
What are the most common 2026 GMC Sierra complaint categories?
ENGINE 16
POWER TRAIN 5
POWER TRAIN,ENGINE 5
ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM 1
ENGINE,FORWARD COLLISION AVOIDANCE 1
ENGINE,FUEL/PROPULSION SYSTEM 1
EQUIPMENT 1
FORWARD COLLISION AVOIDANCE 1
FORWARD COLLISION AVOIDANCE,LANE DEPARTURE 1
POWER TRAIN,ELECTRICAL SYSTEM,ENGINE 1
45 total complaints on record
Latest complaints
| Date | Component | Summary | Severity | Mileage |
|---|---|---|---|---|
| Feb 2026 | EQUIPMENT | 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 | Unknown |
| Feb 2026 | ENGINE,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 | Unknown |
| Feb 2026 | POWER TRAIN,ELECTRICAL SYSTEM,ENGINE | 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 | Unknown |
| Feb 2026 | POWER 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 | Unknown |
| Feb 2026 | POWER 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 | Unknown |
| Feb 2026 | POWER 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 | Unknown |
| Feb 2026 | ENGINE | 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 | 6,000 |
| Feb 2026 | ENGINE | "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 | Unknown |
| Jan 2026 | ENGINE | 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 | Unknown |
| Jan 2026 | POWER TRAIN,ENGINE | 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 | Unknown |
| Jan 2026 | FORWARD COLLISION AVOIDANCE,LANE DEPARTURE | 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 | Unknown |
| Jan 2026 | POWER TRAIN,ENGINE,FUEL/PROPULSION SYSTEM | 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 | Unknown |
| Jan 2026 | POWER 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 | Unknown |
| Jan 2026 | ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM | 2026 Sierra 1500 AT4 with 3.0L Duramax Diesel. Three major issues. 1. 2960 miles, thrust bearing failure caused low oil pressure and internal damage. Vehicle needs complete engine replacement. The truck is still at the dealer with no ETA on engine arrival and replacement. 2. Vehicle has severe electrical issues. battery replaced on second day of ownership due to over charge and smoking. The truck would randomly lose the ability to produce sound through infotainment system on start. This includes warning sounds and audible turn signal sound. Dealer said it’s caused by faulty Amp which was replaced. 3. The truck shut off (full system shutdown) and the transmission failed over to neutral while driving on the highway and failed to restart. Barely restarted on second attempt. Dealer has no idea why it is doing it. However the vehicle was throwing multiple code related to transmission module failure, brake module failure, transmission module failure, etc. | Crash: No Fire: No | Unknown |
| Jan 2026 | ENGINE | 3.0 Duramax Engine Failure - 2026 GMC Sierra 1500 Denali Ultimate at just 6,755 miles and only 77 days of ownership. Within the first few thousand miles, the truck intermittently had warnings appear of “reduced acceleration, drive with care”. The truck would limit its ability to maintain speed. When it occurred during highway driving, it was particularly dangerous. The check engine light would also come on. After parking the vehicle for a bit and restarting it, things returned to normal. At the dealership, we reported the issue and leaned the computer reveled a P06DD code which required them to check the crankshaft for excessive play. Our truck was out of specification requiring complete engine replacement at just 6,755 miles. “Service Bulletin 25-NA-307 which states this code may set due to thrust bearing failure. following 25-NA-307 checked crankshaft end play and got a reading of 0.3400 in. the maximum spec is 0.0124 in.“ GM and Laura Buick GMC should not have sold this truck to us without inspecting it for this known issue. This extensive repair required complete removal of the cab from the chassis. | Crash: No Fire: No | Unknown |
| Dec 2025 | POWER TRAIN | My 2026 GMC 1500 is equipped with the 2.7L L3B & 8L90 Transmission. At approximately 1000 miles, I noticed that in 2nd between 2700-3200 RPM, a vibration could be felt throughout the cabin and would occur whether with or without throttle application. I am able to recreate the issue during hard acceleration or placing in manual mode. No matter the Vehicle mode selection (sport, normal, snow, tow/haul, etc.), the issue still persists. I took the vehicle to a local GMC dealer at approximately 6K miles to diagnose. I requested that we test drive another 1500 with the same 2.7L and Transmission. They brought out a 2026 Elevation Quad Cab with the 2.7L; less than 20 miles on the odometer.The same vibration was present in 2nd gear at same RPM band. I requested that the issue be escalated to a local GM rep. for further investigation. However the response from the dealer was inadequate and basically stated that no warranty work would be considered because it seems to be “normal operation”. | Crash: No Fire: No | Unknown |
| Dec 2025 | UNKNOWN OR OTHER | I saw the report regarding models of Chevrolet trucks not receiving owners manuals from factory. I purchased a 2026 GMC AT4 in early October 2025. It didn't come with a manual either. I emailed my sales person at Ewing GMC in Plano, Texas informing him that it was missing the manual and I was told that GM had decided to only include physical manuals with Denali grade trucks. This didn't make any sense whatsoever. I would prefer to have a physical manual available to reference in the event of vehicle issues. | Crash: No Fire: No | Unknown |
| Dec 2025 | SERVICE BRAKES, HYDRAULIC,ELECTRICAL SYSTEM | The contact owns a 2026 GMC Sierra 1500. The contact stated that upon starting the vehicle and shifting into reverse(R), the vehicle failed to move while depressing the accelerator pedal. The contact felt a hesitation while depressing the brake and accelerator pedals, and the contact then attempted to restart the vehicle. The contact restarted the vehicl;e however, while attempting to accelerate, the brakes independently activated. Despite the repeated failure, the contact was able to pull into a gas station to restart the vehicle. The contact stated that after several attempts, the vehicle finally resumed normal operation, and the contact drove the vehicle to the residence. The next day, the contact test drove the vehicle, and the failure reoccurred while the contact was attempting to park the vehicle in a parking spot. The vehicle was taken to a dealer, where a diagnostic test produced 7 fault codes; however, the mechanic was unable to repair the vehicle. The manufacturer was notified of the failure, and the manufacturer stated that there was a communication disconnect between the contact and the dealer. A case was filed with the manufacturer. The vehicle was not repaired. The failure mileage was approximately 300. | Crash: No Fire: No | 300 |
| Oct 2025 | ENGINE | I do not have an official communication from the dealer who is servicing my vehicle. However, they have had my vehicle for almost 3 weeks and they tell me that the engine has failed and needs complete replacement. They said the engine lost compression and quit running, it now cranks and does not start. Although the engine has not been disassembled we believe the point fo failure to be in the rotating assembly of the bottom end of the engine. | Crash: No Fire: No | Unknown |
| Sep 2025 | UNKNOWN OR OTHER,VISIBILITY/WIPER | Ac not working properly. Ac blows air to defrost vents foging front windshield and side windows causing bad visibility | Crash: No Fire: No | Unknown |