2026 GMC SIERRA 1500 Complaints

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)

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.

On or about 12/14/25 at approximately 2,000 miles my engine began smoking to the point that it was pushing in to the interior of the cabin and created a cloud like atmosphere that smelled of burning oil. There were no warning messages in the vehicle or in the mobile diagnostic application associated with the vehicle. Once parked, I popped the engine and observed visible smoke from the engine and a distinct crackling noise coming from the area of the engine. I checked underneath the vehicle and was able to see oil dripping and, subsequently, feel oil running down a majority of the undercarriage of the truck. Ultimately, I had the vehicle towed the dealership and they diagnosed a front cover seal for the engine was leaking and repaired the issue. On 3/20/26 I had to take my vehicle in for an early oil change due to the above issue and low oil life. Since the above repair, I had continued to smell intermittent burning oil in the cabin of the truck. During the oil change I asked the GM service provider to check to ensure the same issue had not recurred and, following the oil change, I was informed they did not see any issue. On 5/8/26, at approximately 7,000 miles, the same issue regarding visible smoke in the cabin occurred and, upon opening the hood, I was able to see visible smoke from the engine and hear the same crackling noise. I checked underneath the vehicle and, again, was able to see oil dripping and feel it on a majority of the underside of the truck. There were no warnings, in the vehicle or in the GM app for the vehicle, associated with the failure. Again, I took the vehicle to the GM dealer service center. The diagnosis was a leaking rear cover seal. Upon repairing this issue, GM service discovered "flakes" in the oil in the engine and diagnoses a failing thrust bearing that indicated engine failure. I have documentation of the diagnosis and attempted repairs but, am not currently in a location that I can scan and upload them. I can provide them.

The engine started having knocking and I took it to the dealership and now I have been waiting 45 days with no engine replacement in site after they told me the engine failed completely. It had 3,900 miles on the engine!

I bought the truck brand new from Gregg Young in Atlantic, IA. While an hour into the drive home, the truck began shuttering as if the transmission was having problems finding the gear. I immediately made an appt with their parent dealership of Gregg Young in Plattsmouth, NE. They had the truck for a week and couldn’t duplicate the transmission issues after I reported several occurrences and symptoms, they also didn’t provide a service invoice of the work performed while I found was unusual. As I was driving the truck home from repairs it started hesitating and having difficulty finding gears. I didn’t think much of it since the dealer claimed there was nothing wrong. This past weekend while going 65 mph down the freeway the transmission started shuttering as well as the truck and the tires began to lock up to the point of almost losing control, there was also metal on metal noises. I had to pull over and luckily driving real slow I made it home. The Gregg Young dealership were I bought it will take no responsibility and provided falsification since no service was provided nor upon checking app gps there was no indications it left the dealership while in there possession for a week, will contact GMC in the AM since this has now become a safety issue and there was metal on metal contact noises and the serious risk of a crash.

Vehicle keeps displaying a warning message to service drivers assistance system. Taken the vehicle to the dealership multiple time and the condition still persists. Dealership contacts GM tech support and are being told that GM is aware of the problem, programing issue, but they have no solution after several months. Multiple vehicles at many dealerships have the same problem. I don't feel safe driving the vehicle. Drivers assistance system includes multiple cameras and sensors. This condition could cause severe accidents of even death if the system gives false or wrong information

Driving on the PA turnpike at speed with traffic and the engine lost power and started squealing. No lights came on, I was able to get to the side of the road and the truck shut off. When I restarted it, it sounded terrible. Had it towed to dealer and dealer stated that the engine had a terminal failure with the crank bearings and needs replaced. I was fortunate at the time of the issue that I was able to get off the road since the truck lost all power.

Complete engine failure at 1838 miles. Need complete engine replacement. Estimated time unknown for replacement parts.

The motor on my 2026 GMC Sierra stalled 2 weeks ago with a p0016(crankshaft position sensor issue). Was able to clear code and limp home. Vehicle did stall on a busy road and stop abruptly. Scheduled service and was advised to drive it in. Was experiencing irregular idle when warmed up, and a slight hesitation in the pedal. Service advisor started the vehicle and claimed no codes, and everything appear OK. Later in the afternoon the service advisor called to inform me that the vehicle had a siezed engine and had siezed during a test drive on the highway. Currently waiting on warranty information, and engine replacement information but i've been informed it will require a whole new engine. This is the same 6.2l L87 V8 that has been in near constant recalls from GMC over the last 6 years.

Driving approximately 30mph, the engine shut down. Vehicle shifted into neutral until stopped and shifted to park. Unable to place in neutral to pull off the road. Check engine stated transmission needed service. Dealership states seized engine. Engines are on back order. Vehicle has 2980 miles on the odometer. I'm active duty Navy and have a permanent change of station this summer and no vehicle to move in and I also haven't gotten a rental.