{"nhtsa_id":604092,"type":"service_bulletin","type_name":"Service bulletin","date_added":"1999-04-12","date":"1999-02-19","document_id":"SB541002","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV)","mfr_system":null,"summary":"SUBJECT ON INSTALLATION OF NEW-STYLE HEIGHT CONTROL VALVE FOR AL SUSPENSION ORIGINALLY BUILT WITH HEIGHT CONTROL VALVE AND SEPARATE PILOT DUMP VALVE. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/604092","components":[{"id":"engine","name":"Engine","parent":null},{"id":"exhaust-emissions","name":"Exhaust and emissions","parent":null},{"id":"pcv","name":"Crankcase ventilation (PCV)","parent":"exhaust-emissions"}],"codes":[],"topics":[],"vehicles":[{"make":"MACK","model":"CH","year_from":1999,"year_to":1999,"match":"exact","vehicle_ids":["1999_mack_ch"]},{"make":"MACK","model":"CL","year_from":1999,"year_to":1999,"match":"exact","vehicle_ids":["1999_mack_cl"]},{"make":"MACK","model":"MR","year_from":1999,"year_to":1999,"match":"exact","vehicle_ids":["1999_mack_mr"]},{"make":"MACK","model":"RD","year_from":1999,"year_to":1999,"match":"exact","vehicle_ids":["1999_mack_rd"]}],"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":[]}