Feds Expand Probe Into GM’s V8 Engine Failure Issue

Not a Good Year for General Motors

GM has been dealing with a problem under the hood, specifically, the ubiquitous 6.2-liter L87 V8 engine. Used in models such as the Chevrolet Silverado, GMC Sierra, and Cadillac Escalade, the L87 has been linked to engine failures across hundreds of thousands of vehicles in the US.

Following complaints from owners, the National Highway Traffic Safety Administration (NHTSA) opened a formal investigation in early 2025. The move led to one of GM’s biggest recalls in recent years, targeting over 877,000 vehicles built between 2019 and 2024.

Now, the agency is taking the next step. Despite the recall, new complaints have surfaced, prompting the NHTSA to expand its probe to include about 286,000 more vehicles, according to Reuters. It’s now conducting an engineering analysis – the most advanced level of safety investigation – to determine if GM’s proposed fixes are sufficient and whether the issue extends to models outside the initial recall.

A Growing Federal Investigation

The deeper investigation followed the NHTSA receiving more than 1,100 reports of bearing failure in L87 engines. The defect involves the connecting rods, crankshaft, and engine bearings, which can fail prematurely, resulting in a complete loss of power. Some cases happened at highway speeds, while others occurred almost immediately after delivery.

GM’s response has been a partial fix. Vehicles with the P0016 trouble code are inspected, and those that pass receive an oil change to a thicker 0W-40 formulation, along with a new filter, cap, and updated manual entry. Vehicles that fail the test are quarantined until further notice. What began as a preliminary evaluation in January evolved into a large-scale recall by April and a flurry of lawsuits by midyear.

How’s It Been So Far

The L87’s problems first emerged in 2023, with owners reporting failures and even fires – some occurring while on the highway. By January 2025, federal regulators began investigating, which led to the aforementioned recall by spring. The succeeding lawsuits after the recall and the remedy aren’t helping the automaker’s case.

With the NHTSA having upgraded the case to an engineering analysis, the agency is looking for a deeper issue that is not covered by the recall. Yes, GM continues to cooperate with the agency, but with growing complaints and production challenges for replacement engines, the issue may take months – if not longer – to resolve.