{"nhtsa_id":10002749,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2003-09-12","date":"2002-12-12","document_id":"121202","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:ENGINE","mfr_system":null,"summary":"ENGINE BACKFIRES WITH SUFFICIENT FORCE TO DAMAGE THE ENGINE AIR INTAKE SYSTEM AND THE AIR CLEANER FILTER ELEMENT. CERTAIN CHEVROLET AND GMC MEDIUM DUTY TRUCKS AND SCHOOL BUS CHASSIS. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/10002749","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"CHEVROLET","model":"C SERIES","year_from":1999,"year_to":2000,"match":null,"vehicle_ids":[]},{"make":"GMC","model":"C SERIES","year_from":1999,"year_to":2000,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}