{"nhtsa_id":10204624,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2021-12-13","date":"2021-07-01","document_id":"SIB330321","mfr_campaign":null,"replaces":null,"component":"POWER TRAIN:DRIVELINE:DIFFERENTIAL UNIT","mfr_system":null,"summary":"During the vehicle's operational life, normal gear oil seepage or sweating, in addition to accumulated road dust, dirt and grime under the vehicle can give an appearance that there is an active rear differential oil leak. This is further exaggerated by residual oil that remains on the rear differential cover after maintenance services are performed. If this visual appearance of accumulated oil on the rear differential is misinterpreted as an active engine oil leak, then unnecessary seal/gasket repairs/replacements will result.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2021/MC-10204624-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2021/MC-10204624-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/10204624","components":[{"id":"powertrain","name":"Transmission and driveline","parent":null},{"id":"differential","name":"Differential","parent":"powertrain"}],"codes":[],"topics":[],"vehicles":[{"make":"BMW","model":"BMW","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":[]}