The National Highway Traffic Safety Administration has opened an engineering analysis covering 997,743 General Motors trucks and SUVs after regulators found engines that had already been repaired or replaced under a 2025 recall were failing all over again. The agency’s Office of Defects Investigation designated the case EA26005 on August 20, 2026, expanding a probe that started with a single information request seven months earlier into one spanning six years of production.
At the center of the case is GM’s naturally aspirated 6.2-liter V8, known internally as the L87, an engine fitted to some of the company’s highest-volume vehicles. The vehicles covered include the Chevrolet Silverado 1500, Tahoe, and Suburban, the GMC Sierra 1500, Yukon, and Yukon XL, and the Cadillac Escalade and Escalade ESV, spanning the 2021 through 2026 model years.
The original recall covered 597,630 trucks, with 3 percent expected to need a new engine
GM’s own Part 573 safety recall report, filed with NHTSA on April 24, 2025, put the affected population at 597,630 vehicles built between March 1, 2021, and May 31, 2024, and estimated that 3 percent of them had the underlying defect. The filing traces the problem to two supplier manufacturing issues: rod-bearing damage caused by sediment left inside connecting rods and crankshaft oil galleries, and crankshafts machined outside the required dimensions and surface finish. Either defect, GM said, can cause the engine to lose propulsion while the vehicle is being driven, raising the risk of a crash.
The recall, designated 25V-274, sent every affected vehicle through a dealer inspection. Engines that failed were fully replaced; engines that passed were switched to a thicker 0W-40 oil and given a new oil filter, oil-fill cap, and owner’s manual insert rather than a new block. GM’s filing shows the split by model: 153,630 GMC Sierra 1500s, 107,244 Chevrolet Silverado 1500s, 82,832 GMC Yukons, 79,747 Cadillac Escalades, 60,933 GMC Yukon XLs, 46,280 Escalade ESVs, 44,802 Chevrolet Tahoes, and 22,162 Chevrolet Suburbans.
GM had already logged 28,102 related complaints before the recall
GM’s chronology inside the same filing shows the company had been aware of the pattern for years before it acted. The automaker closed three earlier internal investigations into L87 engine failures in February 2022, June 2023, and July 2024 without finding enough to justify a recall, only opening a fourth review on January 16, 2025, after NHTSA itself flagged the issue. That review turned up 28,102 field complaints tied to crankshaft, connecting-rod, or bearing failure, of which 14,332 alleged a full loss of propulsion, plus 12 related crashes, 12 related injuries, and 42 fire allegations, most of them confined to engine-compartment damage consistent with a failed engine rather than a separate ignition source. GM’s safety board approved the recall three months later, on April 17, 2025.
Reimbursement for owners who paid for related repairs before the recall was folded into the same filing, and dealer notifications began April 24, 2025, with owner letters following in June. Nothing in the report suggested regulators expected the story to reopen within a year of the fix going out.
NHTSA’s Sharon Yukevich reopened the case after 139 post-repair failures
It did reopen. In a February 17, 2026, information request addressed to GM engineer Jeffrey Ronne, Sharon Yukevich, chief of the Office of Defects Investigation’s Vehicle Defects Division A, told GM that her office had received 139 reports of L87 engines failing in Silverado, Suburban, Tahoe, Sierra, Yukon, Yukon XL, Escalade, and Escalade ESV models after they had already gone through the recall’s remedy. Yukevich’s letter opened a formal recall query, given the case number RQ26-001, and demanded vehicle-by-vehicle production data, warranty claims, and GM’s own assessment of why engines that had passed inspection or received full replacements were failing anyway. GM had until April 3, 2026, to respond or face civil penalties of up to $27,874 per violation per day.
The complaints Yukevich cited were split between two groups: engines that had received only the oil-viscosity fix and engines that had been fully replaced under the recall. Both categories, per the letter, showed the same knocking, banging, check-engine-light, and no-start symptoms GM had already described as warning signs of the original defect, an overlap that made it hard to dismiss the post-repair reports as unrelated new problems.
The reopened probe now spans 997,743 vehicles and 690 new failure reports
By the time NHTSA escalated the case to a full engineering analysis six months later, the numbers had grown substantially. According to GM Authority’s reporting on the EA26005 filing, the Office of Defects Investigation had by then received 499 complaints alleging failure after the recall remedy, 473 of them involving engines that got the oil-viscosity fix and 26 involving engines that had already been fully replaced. A separate 191 failures involved L87 engines built after the original recall’s May 2024 cutoff, pushing the combined total of new failure reports to 690 and prompting NHTSA to widen the population from the recall’s 2021-2024 build window to every L87-equipped truck and SUV built through the 2026 model year.
That expansion is what pushed the population past the symbolic million mark: 997,743 vehicles now sit inside an open federal engineering analysis, the stage NHTSA uses just before deciding whether to order a manufacturer to expand or reissue a recall. GM’s dealer network continues to run the same two-track remedy, an oil-and-filter swap for engines that pass inspection and a full replacement for those that do not, even as the failure reports pile up inside the same population the company already tried to fix once.
Neither GM nor NHTSA has said publicly whether the engineering analysis will result in a second recall, a recall expansion, or a finding that the original remedy was simply incomplete for a subset of engines. The inspection process that sorted engines into the two remedy tracks in 2025 is the same process regulators are now scrutinizing to determine why a meaningful share of engines it cleared, and even some it replaced outright, kept failing afterward.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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