{"nhtsa_id":620028,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2001-07-09","date":"2001-03-20","document_id":"SB539001","mfr_campaign":null,"replaces":"SB539001","component":"SERVICE BRAKES, AIR:ANTILOCK:WHEEL SPEED SENSOR","mfr_system":null,"summary":"IN CERTAIN OPERATING CONDITIONS, FAULT CODES FOR EXCESSIVE SPEED SENSOR AIR GAP / SENSOUR OUT OF ADJUSTMENT AT THE REAR DRIVE AXLE MAY BE LOGGED REPEATEDLY ON CHASSIS EQUIPPED WITH S440, S441 OR S462 REAR DRIVE AXLES. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/620028","components":[{"id":"brakes","name":"Brakes","parent":null},{"id":"abs","name":"Anti-lock brakes","parent":"brakes"},{"id":"wheel-speed-sensor","name":"Wheel speed sensor","parent":"brakes"}],"codes":[],"topics":[],"vehicles":[{"make":"MACK","model":"MACK","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":[]}