ISF3.8 Cummins Oil Seal 5259499 Parts Catalog Ref No. Part Name Part No. Required 1 Flywheel Housing 4935815 1 2 Rear Cover Gasket 4947667 1 　 Rear Cover 5266600 1 　 Rear Cover 3936895 1 3 Oil Seal 5259499 1 　 Hexagon Flange Head Cap Screw 3991306 6 　 Crankshaft Seal Kit 5264562 A/R 3 Oil Seal 5259499 1 　 …