2021 GMC Sierra 1500 engine complaints

Filed Feb 19, 2021 · Engine, Fuel system · 2,500 miles · OK

While driving during winter conditions with temperature at 3 degrees on a residential street with limited traffic, the diesel fuel in the fuel filter gelled up which caused the vehicle to display reduce power mode and then immediately shut off and would not start. The vehicle coasted to a stop in the middle of the street while in traffic. The owners manual lists utilizing top tier diesel which I did. While additives are not normally needed in most states to fuel for freezing conditions evidently they are needed in oklahoma. The fuel filter housing is the only place where the fuel gelled up, which appears to be a theme in most gmc diesel trucks and does not effect fuel in the fuel tank due to volume. Gmc has done nothing to improve the design or increase insulation to the thin fuel filter housing. If I had been in fast traffic on the interstate it would have resulted in an accident and possible loss of life.

Filed Dec 15, 2020 · Engine · 625 miles · OR

The vehicle was bought brand new and was only driven for a week. It was in motion on the freeway when the engine started to sound noisier than usual, like that of an older truck. It was hard to notice on higher speeds on the freeway, but upon slowing down on curves, it got more obvious that something was really wrong because the noise sounded like something was loose inside the engine. There was no 'check engine' light or any other warning lights. Upon exiting the freeway, the engine shut off completely while in motion. Fortunately, I was able to pull in a parking lot and park it safely. The engine would not start safely after that, and 'check engine' activated. The vehicle is currently being diagnosed at a dealership. Last update was that the engine was being taken apart completely because they said it's definitely inside it.