6CT8.3 Cummins Main Bearing 3944158 Parts Catalog Ref No. Part Name Part No. Required Crankshaft , Assembly Top Level Assembly 3918986 1 Pin Dowel 3904483 1 Engine Crankshaft 3917320 1 Crankshaft Gear 3918776 1 Crankshaft Thrust Bearing 3944163 1 Main Bearing 3944153 7 Pin Dowel 3901846 2 Expansion Plug 3901969 1 Pipe Plug 3906619 6 Rectangular Ring Seal 3907177 …