NHTSA Escalates GM Brake Probe: Field Reports Contradict GM's Root Cause

NHTSA upgraded its GM brake investigation to an engineering analysis after field reports of immediate brake-assist loss remained inconsistent with GM's identified root cause of eBoost spindle fractures. The discrepancy suggests an additional, uncharacterized failure mode. The probe covers over 1 million vehicles linked to hundreds of incidents, 20-plus crashes or fires, and at least six injuries.