NHTSA GM L87 Engine Probe Targets 997,743 Vehicles

On August 20, the U.S. National Highway Traffic Safety Administration (NHTSA) announced that its Office of Defects Investigation (ODI) had opened a NHTSA GM L87 engine probe involving 997,743 General Motors pickups and SUVs over concerns related to engine failure. The affected vehicles include the Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban and Tahoe, and GMC Sierra 1500, Yukon and Yukon XL, covering model years 2021-2026 and equipped with GM's L87 engines.

Investigation Expands After Earlier Recall

ODI said it received 499 complaints alleging engine failures even after the affected vehicles had undergone an earlier recall remedy under Recall 25V274. Of those complaints, 473 involved an oil viscosity change, while 26 involved a complete engine replacement. General Motors issued the recall in 2025 to address concerns involving failures of its L87 engine and attributed the issue to a supplier's manufacturing process. The new investigation will examine whether engine failures continued despite the actions taken under that earlier recall.

Reports Include Engines Produced After Recall Period

In addition to complaints involving vehicles that received the earlier remedy, ODI has received 191 reports of L87 engine failures involving engines produced after the production period identified in Recall 25V274. United States regulators said the expanded scope is intended to assess these additional reports alongside post-remedy failures. General Motors separately reported receiving 6,953 complaints involving post-remedy engine failure, adding to the volume of information being considered as the investigation proceeds.

NHTSA to Continue Engineering Analysis

NHTSA said its new engineering analysis will continue investigating complaints involving post-remedy engine failures and will expand the investigation to include engines produced after the production period cited in the recall. The agency's work is therefore focused not only on vehicles that underwent the previous remedy but also on whether similar failures occurred in later-produced L87 engines. The findings could help determine the scope and underlying circumstances of the reported engine failures as the engineering analysis continues.

Frequently Asked Questions

What is NHTSA investigating in General Motors vehicles?
NHTSA is investigating reported L87 engine failures involving 997,743 General Motors pickups and SUVs from model years 2021-2026. The investigation follows complaints alleging engine failures after vehicles received a remedy under Recall 25V274, including cases involving an oil viscosity change and complete engine replacement. The agency has also received reports involving L87 engines produced after the production period covered by the earlier recall. NHTSA said its engineering analysis will continue examining post-remedy failures while expanding the investigation to include later-produced engines and additional complaints.