2015 GMC Sierra 1500 Owner Complaints

The transmission Started Shuddering, it would slip occasionally and slipped badly when i was driving in rush hour traffic in the middle of a left turn. had no power for several seconds then it finally reengaged. The shuddering got worse and worse to the point i took it to a transmission shop to look at it and they said i needed a replacement transmission unit. I did get a replacement unit, the whole process was extremely unpleasant. The previous unit was sent as a core to be remanufactured. The company that i used to get a remanufactured unit is Fraser Transmissions. No warning lamps appeared prior to the transmission acting up.

NHTSA ID

11766154

Incident

Jul 18, 2025

Power steering seems to be lost for a second or two at low speeds turning. Happens multiple times a day.

NHTSA ID

11763463

Incident

Sep 10, 2026

My 2015 GMC Sierra 1500 recently started having all the symptoms under GM internal recall number 18289. I lose my power steering briefly and the electronics turn off momentarily. I lose dash, AC, radio and GPS. It comes back on within a second or two and only does this during low speed turning. I ran my VIN but it does not show under this recall despite having the correct Make/Model/Year. It is currently at the shop because it isn't safe to drive and I was hoping I could get a reimbursement for the repairs. NHTSA Campaign Number: 18V586000 (GM's Internal Number: 18289)

NHTSA ID

11760877

Incident

Jun 15, 2026

See attached document for complaint.

NHTSA ID

11758571

Incident

Jun 6, 2026

From time to time since I got the vehicle, the lights flicker inside and out. I've had the alternator changed but it continues. Then when pressing the lock button on the key fob the horn sounds as if it has a shortage. Sometimes its loud and sometimes it's barely heard.

NHTSA ID

11758124

Incident

Dec 5, 2023

My 2015 GMC Sierra 1500 SLE has the 6L80 transmission. While traveling on the interstate with my fiancé, the transmission failed. It was towed to a garage and they informed me that it needed to be replaced.

NHTSA ID

11755314

Incident

Nov 11, 2025

my rear window defrost turned on when i auto started my pickup. i realized it was on after about a half hour and looked back and my drivers side of the rear sliding window was shattered completely

NHTSA ID

11749832

Incident

Nov 15, 2025

When backing up, either on a hill or flat surface, the brakes fail to stop the vehicle. There is a pulsing sensation with the brakes due to failure of the vacuum. The brake pedal also becomes impossible to depress. No warning lights appear when this occurs.

NHTSA ID

11748839

Incident

May 1, 2026

The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at 25 MPH, the front driver's seat belt completely failed. The lap belt portion came apart, causing the chest strap to loosen. Upon inspection, the contact observed that the steel anchor cable bolted to the floor had separated. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 153,000.

NHTSA ID

11742780

Incident

Jun 7, 2026

Mileage

153,000 mi

For no apparent reason the truck goes into “low power mode” and gives off code p2138 often happens around 30-35 mph. Have had it happen to me also around 45 mph also. I have replaced sensors and parts to which a month or so goes by and it happens again.

NHTSA ID

11740204

Incident

May 26, 2026

Vehicle doesn't stop in low speeds

NHTSA ID

11738356

Incident

May 11, 2026

The contact owns a 2015 GMC Sierra. The contact stated that while driving at an undisclosed speed and also while the vehicle was parked, the ABS and stability control warning lights would unexpectedly illuminate. The vehicle was taken to an independent mechanic, where the warning lights were cleared. The contact was informed that if the failure recurred, the EBCM and BPMV would need to be replaced. The vehicle was not repaired. The contact stated that the failure recurred. The vehicle was then taken to the dealer, where it was diagnosed that the EBCM and BPMV had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 90,100.

NHTSA ID

11737603

Incident

May 13, 2026

Mileage

90,100 mi

Active Fuel Management Miss firing Idle rough Shaking Loss of power #7 cylinder loss of all compression Bad fuel mileage Skipping

NHTSA ID

11732442

Incident

Apr 9, 2026

The contact owns a 2015 GMC Sierra 1500. While traveling on a two-lane highway at approximately 55 MPH, another vehicle suddenly turned into the contact's lane, resulting in a severe frontal "T-bone" collision. The force of the impact caused the other vehicle to be propelled into a ditch, while the contact's vehicle remained on the roadway. Despite the significant nature of the crash and the speed involved, no air bags deployed. The dealer was notified of the failure. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 218,000.

NHTSA ID

11728045

Incident

Mar 21, 2026

Mileage

218,000 mi

Bad paint used by manufacturers that causes frames to rust out.

NHTSA ID

11726320

Incident

Mar 22, 2026

Truck started to make loud clunking noise when driving taken it to two shops and wrong parts were installed as stated below. Bought from a used car dealership and they sold it as is now with the wrong parts.

NHTSA ID

11726316

Incident

Mar 23, 2026

The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at approximately 45 mph, he observed a popping noise beneath him. The contact stopped the vehicle and observed smoke emanating from the front of the vehicle. The vehicle went into limp mode, lost power, and when the brake was depressed, the vehicle did not slow the vehicle down as intended. The contact stated that as he pulled into a parking lot to inspect the vehicle, he observed flames emanating from the hood. The contact stated that he pressed the hood latch, which did not open the hood, and he then exited the vehicle and observed the hood engulfed in flames. The contact mentioned that a store employee brought a fire extinguisher out and attempted to extinguish the flames. The fire department was called and extinguished the fire fully. There was no police report, but the police did come out to assist. The contact sustained a right-hand injury, but medical attention was not needed. The vehicle was then towed to the residence. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was 124,000.

NHTSA ID

11724912

Incident

Mar 13, 2026

Mileage

124,000 mi

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.

NHTSA ID

11722758

Incident

Mar 4, 2026

I had and still have the Brake Assist failure warning light on and having issues with brake pedal effort not working as it should to stop vehicle and also the stability control warning lights., the brakes hardly work at all at low speeds and most of the time don't stop the vehicle almost causing several crashes. I took vehicle to gm service center and they said they updated software but when I picked up the vehicle and drove it not long after the brake assist warning came back on and I still had no brakes at slower speeds and the problem had actually gotten worse than it was before i took it to them. I called the dealership and told them that the problem had not been fixed and it was worse they said that I would have to pay the service fee / price for parts if I wanted to bring the vehicle back in and to have problem fixed...I explained it was a re call and it was taken to them to have issue fixed in the first place ...and I was told I would have to pay since they updated software ..I then explained it was worse than when I took it to them and still got denied any kind of resolution to the problem. Nothing was fixed or solved. I still had the warning lights on dash and the problem was worse then when I took the vehicle to them for repair. Not long after the transmission went out and the vehicle hadn't been drove. So it sat for 2 yrs or so. I just got a new one put in and the vehicle still has the same problems with the brake system . I reached out to dealership once again and was told I would still have to pay to have the issues fixed when it was never taken care of by them to begin with.

NHTSA ID

11721467

Incident

Nov 30, 2023

I remote started my truck, and when I got to it there was smoke and a flame coming from the rear power window. The remote start activates the rear defrosters, which started the electrical issues. I shut off the engine, and a loud pop followed, which was the shattering of the driver side rear window. The flame went out, and could have easily ignited the tarp covering the truck bed. There were no warnings on the console for the issue, and no recalls available. I have seen similar recall, but in a different state and back in 2022. This leaves me with a shattered window in the back, which is unsafe for visibility, and a bill to pay due to manufacturing errors for a feature in the truck. The rear window is all melted, and the glass is chipping away.

NHTSA ID

11720409

Incident

Feb 21, 2026

The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the brake pedal was firm and unresponsive, and the vehicle was difficult to stop. The vehicle eventually came to a stop with the ABS warning light illuminated. The vehicle was driven back to the residence. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 132,235.

NHTSA ID

11718801

Incident

Jan 1, 2026

Mileage

132,235 mi

During day to day driving when the truck is accelerating from a stopped position there's a massive clunk or hard shift from either 1st to 2nd gear. have also heard similar complaints from other 2015 sierra 1500 owners saying the transmission is having a hard shift on acceleration from a stop. Have seen possible issues with the TCCM

NHTSA ID

11718679

Incident

Aug 9, 2025

Tranmission is shuttering and not wanting to shift right

NHTSA ID

11718485

Incident

Jan 1, 2026

The contact owns a 2015 GMC Sierra 1500. The contact stated that while at a complete stop and attempting to shift into reverse(R), Drive(D) or park(P), the gear shifter was stuck, and the contact had to go underneath the vehicle to move the shifter cable into the intended gear. The vehicle was taken to an independent mechanic, where the upper and lower shifter cables were replaced. The contact stated that upon returning to the residence and attempting to park the vehicle, the gear shifter failed to remain in the intended gear and was moving unintendedly. The vehicle was not repaired. The dealer and the manufacturer were not contacted. The failure mileage was approximately 225,740.

NHTSA ID

11717007

Incident

Jan 20, 2026

Mileage

225,740 mi

I remote started my truck. I got in about 5 minutes later. When I shut the door the rear window, passenger side of the power sliding window blew out. GM says my VIN is not affected by the recall but my truck shows that it should have been part of the recall or customer satisfaction program. N192265660 Rear Window Defroster Thermal EventS

NHTSA ID

11716665

Incident

Feb 8, 2026