System: brakes; hydraulic; power assist; check valve.vehicle description: light duty pickup trucks equipped with 2.2 l engines.note: if the vehicle IS presented to an authorized dealer on an agreed upon service date and the remedy IS not provided free of charge within a reasonable time or the remedy does not correct the defect, please contact chevrolet at1-800-222-1020, or GMC at 1-810-456-4547. Also, contact the national highway traffic safety administration's auto safety hotline at 1-800-424-9393.