Reuters reported on August 21, 2026, that the expanded investigation covers 997,743 vehicles. NHTSA’s public opening resume for engineering analysis EA25007 lists a narrower investigation population of 286,051 vehicles. Those figures describe different investigation scopes, not conflicting totals.

The agency has not announced a new recall or ordered additional repairs. The vehicles under review are not all confirmed to have a defect.

What changed

NHTSA’s Office of Defects Investigation opened engineering analysis EA25007 to examine potential loss of motive power caused by engine failure. The agency’s document identifies the action as a higher-level review following preliminary evaluation PE25001.

NHTSA says it received 1,157 reports of failures involving bearings in GM’s L87 engine. Of those reports, 173 involved vehicles outside the scope of recall 25V-274, the 2025 safety recall connected to the same engine family.

The agency says it continues to receive a significant number of engine-failure reports involving vehicles outside the recall population. EA25007 is intended to evaluate the scope and severity of the potential problem and assess possible safety issues in vehicles built outside the earlier recall scope.

Which GM vehicles are involved

The agency materials name the Chevrolet Silverado 1500, Suburban and Tahoe; GMC Sierra 1500, Yukon and Yukon XL; and Cadillac Escalade and Escalade ESV. The common connection is the L87 6.2-liter gasoline V8 engine.

NHTSA’s opening resume identifies 2019-2024 model-year vehicles in the earlier investigation scope. GM’s 2025 recall filing covers 2021-2024 model-year vehicles. Owners should check a vehicle identification number rather than assume that a model name or model year alone determines coverage.

How the 2025 recall fits in

GM recalled about 597,630 vehicles under recall 25V-274. In its filing with NHTSA, the company said connecting-rod and crankshaft components could have manufacturing or quality problems that lead to engine damage and failure.

GM said an engine failure during operation could cause the vehicle to lose propulsion, increasing the risk of a crash. The company’s filing cited two primary causes identified through its investigation: rod-bearing damage linked to sediment and crankshaft dimensions or surface finish that were outside specifications.

The recall remedy called for dealers to inspect the engine and, when necessary, repair or replace it. Vehicles that passed inspection received higher-viscosity oil, an oil-filter replacement, a new oil-fill cap and an owner’s-manual insert. GM also described a special coverage program for inspected vehicles that received the oil-related service.

The new engineering analysis does not establish that the 2025 remedy was ineffective. It also does not establish that every vehicle in the broader population is defective or that NHTSA will require an expanded recall.

What the complaint record shows

GM’s recall filing reported 28,102 potentially related U.S. complaints or incidents received through February 3, 2025. The company said 14,332 involved allegations of loss of propulsion.

GM also identified 12 alleged crashes, 12 alleged injuries and 42 potentially related fire allegations. The company said the alleged injuries were minor or non-physical, and that the cause of most reported fires was unclear. These figures are company-reported allegations, not findings by NHTSA that each incident was caused by the engine condition.

What owners should do now

Owners can check for open recalls by entering a vehicle identification number or license plate number in NHTSA’s recall lookup. A dealer can also confirm whether a vehicle received the 2025 recall remedy and explain any available coverage.

GM’s recall materials list possible warning signs including knocking or banging noises, a check-engine light, hesitation, abnormal shifting, reduced propulsion or a no-start condition. Owners who notice those symptoms should have the vehicle inspected promptly and ask the dealer to document the concern.

Keep repair orders, invoices and records of engine problems. Owners can also report safety complaints to NHTSA. Those reports may help the agency assess the scope and severity of the issue as EA25007 proceeds.

Sources

• NHTSA engineering analysis EA25007 opening resume
• Reuters report on the expanded GM engine-failure probe
• NHTSA recall lookup