{"nhtsa_id":51347,"type":"service_bulletin","type_name":"Service bulletin","date_added":"1997-06-27","date":"1997-01-01","document_id":"4914","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:EXHAUST SYSTEM","mfr_system":null,"summary":"TOP EXHAUST STACKS ON FLB COES, FLD CONVENTIONALS, FLL COES, AND CENTURY CLASS VEHICLES ARE INSTALLED AT A 45-DEGREE ANGLE OUTBOARD RATHER THAN FACING STRAIGHT BACK- THIS CONFIGURATION INCREASES EPA NOISE TEST EMISSIONS ON CERTAIN VEHICLES. *JD","document":null,"url":"https://open.wenmarpro.com/bulletins/51347","components":[{"id":"engine","name":"Engine","parent":null},{"id":"exhaust-emissions","name":"Exhaust and emissions","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"FREIGHTLINER","model":"CENTURY","year_from":1997,"year_to":1997,"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":[]}