General Motors’ biggest vehicles equipped with the brand’s biggest engine may have a big problem. The NHTSA in January opened an investigation into the 6.2-liter V-8 engine offered on the top trims of everything from the Chevrolet Silverado 1500 and GMC Sierra pickup trucks to the Chevy Tahoe and Cadillac Escalade full-size SUVs.
The safety agency received at least 346 reports from customers alleging a “sudden loss of motive power” due to an engine seizure. Without warning, the connecting rod can breach the engine block or a bearing can fail while driving. In viral videos, the engines knock and thump like a washing machine with an unbalanced load or, worse, washing a handful of big rocks.
A summons for more information from the NHTSA’s Office of Defects Investigation typically precludes a recall. Nearly half a million of the same vehicles were recalled last November for an issue that caused the rear wheels to lock up, but that was exclusive to GM’s 3.0-liter turbodiesel.
The Silverado and Sierra pickup trucks were redesigned for the 2019 model year, whereas the full-size SUVs in GM’s stable were redesigned for the 2021 model year. It’s curious that the 2025 model year is not included in the investigation since the top V-8 had no stated changes to it.
The NHTSA has given GM until Mar. 28, 2025, to provide a slew of requested information regarding the 6.2-liter V-8. It could amount to a massive and expensive recall. Last July, Toyota decided to fix a recall on the Tundra and Lexus LX600 by entirely replacing its new twin-turbo 3.5-liter V-6.