{"nhtsa_id":46418,"type":"service_bulletin","type_name":"Service bulletin","date_added":"1996-04-25","date":"1995-07-01","document_id":"51F001","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:ENGINE","mfr_system":null,"summary":"WITH THE MACHINED DOWEL METHOD OF INSTALLATION, RESEARCH HAS FOUND THAT FLYWHEEL HOUSING RUNOUT IS WELL WITHIN OLD SERVICE SPECIFICATION OF .010 INCH TOTAL INDICATED RUNOUT (TIR) WHEN CHECKED USING AN ALIGNMENT BAR THROUGH THE CYLINDER BLOCK MAIN BEARING BORES. HOWEVER, WHEN CHECKING FLYWHEEL RUNOUT USING DAIL INDICATOR ON THE CRANKSHAFT REAR FLANGE OR THE FLYWHEEL, RESULTS MAY EXCEED .010 INCH DUE TO FACTORS SUCH AS CRANKSHAFT MOVEMENT WITHIN THE BEARING CLEARANCES AND OTHER VARIABLES. BECAUSE OF THIS SITUATION, FLYWHEEL HOUSINGS ARE BEING REPLACED UNNECESSARILY.","document":null,"url":"https://open.wenmarpro.com/bulletins/46418","components":[{"id":"engine","name":"Engine","parent":null}],"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":[]}