{"nhtsa_id":621666,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2001-09-28","date":"2001-06-13","document_id":"130601","mfr_campaign":null,"replaces":null,"component":"POWER TRAIN:AUTOMATIC TRANSMISSION","mfr_system":null,"summary":"THIS BLUE BIRD SERVICE UPDATE IS IN REFERENCE TO ALLISON TRANSMISSION BROCHURE SE 0607EN SYNTHETIC OIL USAGE AND RECOMMENDATIONS. ALLISON APPROVED SYNTHETIC OIL IS REQUIRED IN ALL ALLISON 2000 AND 2400 SERIES TRANSMISSIONS USED IN BLUE BIRD COMMERCIAL UNITS. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/621666","components":[{"id":"powertrain","name":"Transmission and driveline","parent":null},{"id":"automatic-transmission","name":"Automatic transmission","parent":"powertrain"}],"codes":[],"topics":[],"vehicles":[{"make":"BLUE BIRD","model":"BLUE BIRD","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":[]}