{"nhtsa_id":619026,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2001-05-10","date":"2000-08-30","document_id":"300800","mfr_campaign":null,"replaces":null,"component":"SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:MASTER CYLINDER","mfr_system":null,"summary":"SUBJECT REGARDING A GEL-LIKE SUBSTANCE FOUND IN THE MASTER CYLINDER RESERVOIR IN LARGER TRUCKS, CONVENTIONAL, LARGE TILT AND SCHOOL BUS MODELS. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/619026","components":[{"id":"brakes","name":"Brakes","parent":null},{"id":"brake-master-cylinder","name":"Brake master cylinder","parent":"brakes"}],"codes":[],"topics":[],"vehicles":[{"make":"CHEVROLET","model":"CHEVROLET TRUCK","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]},{"make":"CHEVROLET","model":"MEDIUM DUTY","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]},{"make":"GMC","model":"GMC TRUCK","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]},{"make":"GMC","model":"MEDIUM DUTY","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":[]}