2026 GMC Sierra 1500: engine failure

Filed Oct 6, 2026 · Engine · FL

Engine had catastrophic failure at only 1,433 miles driven. Incident happened on the interstate and truck was required to be towed to the dealer. Dealer said engine replacement is necessary.

Filed Oct 6, 2026 · Electrical, Engine · MD

We bought the vehicle on February 28th and on March10th my husband was driving on his way to work on the I95 highway and the engine shut down. My husband was in the middle of the highway with a speed limit of 65. Traffic was able to slow not to cause any more accidents however he had to be towed and GM replaced the engine. Because it had not been 30 days in the shop. Due to GM abiding by Lemon laws we were not able to qualify for a buy back. We have been fighting with them ever since. I was able to get a reimbursement of my first car payment. However, my husband is a general contractor and is absolutely terrified to accept jobs far away because we don’t know when the truck engine might give up again. All of the charging ports stop working a couple of weeks ago, we had to take it in for repairs. This is a $78,000 vehicle with 4 miles on it when we purchased it. I don’t know what it is worth now because the engine was replaced with in 10days of purchasing it. I need help!!!!!!!!!!

Filed Oct 5, 2026 · Engine · MA

The 6.2L engine died at 8,300 miles. It took the dealership 6 weeks and would not give me a repurchase lease buyback. They put a new engine in, but I’m hearing that they didn’t really fix the problem and this is just a new version.

Filed Oct 5, 2026 · Engine · TX

On September 29, 2026, I was driving my GMC Sierra 1500 on the highway at approximately 15 mph due to construction when the truck suddenly lost acceleration. Engine warning messages appeared, the vehicle automatically shifted into neutral, and the engine completely shut off while I was driving. A message instructed me to restart the engine. I attempted to restart it, and the truck eventually turned back on, although it was difficult to start. I was able to carefully drive the vehicle home. This was extremely concerning because the sudden loss of propulsion and engine shutdown occurred while I was on a highway and could have caused a serious accident, especially at normal highway speeds or in heavier traffic. I took the truck to Cavender GMC on September 30, 2026, for inspection and diagnosis. Still pending on results. I am especially concerned because there are ongoing the federal safety agency investigations, consumer complaints, and litigation involving certain General Motors vehicles and reported engine failures that can result in sudden loss of propulsion. Some reported incidents involving GMC Sierra 1500 vehicles describe symptoms similar to what happened to my truck, including loss of acceleration, shifting into neutral, engine shutdown, warning messages, and the need to restart the vehicle. I understand that my truck may not necessarily be affected by the same issue or included in any lawsuit. However, because of the similarities, I am requesting that GMC and Cavender GMC thoroughly investigate whether this incident is related to any known engine, powertrain, electrical, software, or safety issue affecting this vehicle. I am requesting that the underlying cause be identified and properly repaired before the vehicle is considered safe to return to service. My primary concern is safety, and I need confidence that the truck will not unexpectedly lose propulsion, shift into neutral, or shut off again while I am driving.

Filed Sep 30, 2026 · Engine · OR

I was driving home on the evening of September 12th 2026 and when I exited the interstate and came to a stop at the traffic signal my vehicle died and I had to have it towed. There was no way to flat tow because we couldn’t get it into neutral without the vehicle’s engine running. Once the vehicle’s engine died it would not restart. Had this happened while still on the interstate causing my vehicle to be disabled in the lane of travel it could have been deadly since it was 10 p.m. in the evening and dark outside. Anyhow had the vehicle towed to the dealership for diagnosis and the engine spun #7 rod bearing which ruined the entire engine at just 15,182 miles.

Filed Sep 30, 2026 · Engine · OH

Dealer confirmed 6.2 V8 engine failed at a little over 4000 miles. Dealer stated it was the bottom of the engine. Probably the same failure the 21-24 recall is for.

Filed Sep 28, 2026 · Engine, Fuel system · VA

Truck was sold to me and the dealership said the truck did not have the defect and the oil was changed to a thicker oil as a precaution. 4,000 miles later the engine failed, was diagnosed as catastrophic engine failure due to the known recall, and was replaced, new engine is now making the same rod knocking noise.

Filed Sep 27, 2026 · Engine · SC

2026 GMC Sierra 1500 Denali 6.2L , with 3550 miles; started ticking at 45 MPH and another mile to get home started knocking, had truck for less than a month; no warning lights. I had it towed to the dealer. They said it needed a new engine, no time frame for repair.

Filed Sep 27, 2026 · Engine · SC

2026 GMC Sierra 1500 Denali 6.2L , with 3550 miles; started ticking and another mile to get home started knocking, had truck for less than a month, had it towed to the dealer they said will get a new engine, they can't even five me a time frame for the new engine replacement.

Filed Sep 27, 2026 · Engine · MI

I purchased this vehicle on May 28th 2026. At that time I was told there were no problems with the 6.2L engine. The problems they have had didn't affect the 2026 Denali 1500 6.2L's. After hearing about numerous 25's and 26's engine failures I decided to have my first oil change at 1540 miles. I asked the dealership to give me the oil filter so I could open it and examine it. I found excessive metal in the filter, indicating to me that the engine is failing. I contacted the dealer, they told me to go to GM Customer service. They told me there is nothing they can do unless the check engine light comes on or there is noise in the engine or it blows up. In which case people have reported traffic hazards getting to the side of the road without power or even the rear wheels locking up. One incident shows the vehicle had a fire and completely burned up. I made a vacation trip without incident and put another 825 miles on the truck, at which time I swapped out the oil filter and opened it up and found more metal particles. Common sense tells me that the engine is self destructing and will at some point fail. The manner in which that happens is the safety issue. I have reported this issue to the dealer and GM and they say just keep driving it. Putting myself and my family at risk. I know I am not the first one to have a bad engine in my new GMC Denali. There are just way too many defective engines in these vehicles to feel safe after buying such and expensive vehicle. Don't get me wrong, I love the truck!! I just would like to know it has a dependable engine to keep me safe while driving it!!

Filed Sep 26, 2026 · Engine · WI

With 10000 miles on my 6.2 liter the engine failed. Cause was main bearing failure. Needed full engine replacement.

Filed Sep 20, 2026 · Engine · NM

Engine blew on a 2026 GMC AT4X with the 6.2 motor. Has been inspected and confirmed by dealership. No warning on failure, was passing a car when power was lost and warning system said restart engine.