{"nhtsa_id":10020429,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2006-10-02","date":"2007-01-01","document_id":"133","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:ENGINE","mfr_system":null,"summary":"INCORRECT CAT C15 AIR COMPRESSOR DISCHARGE LINE FITTING. MODEL CONSTELLATION. THE TWO PIECE DISCHARGE LINE FITTING ON SOME BENDIX BA-921 AIR COMPRESSORS USED ON CAT C15 ENGINES MAY VIBRATE LOOSE CAUSING AN AIR LEAK AT THE CYLINDER HEAD. WESTERN STAR. *KB UPDATED ON 09/27/07. *NJ","document":null,"url":"https://open.wenmarpro.com/bulletins/10020429","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"UNKNOWN","model":"UNKNOWN","year_from":null,"year_to":null,"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":[]}