Description

The Cummins Fractured-Cap Connecting Rod Bearing RB-3945918 (0.25 mm undersize) is an OEM-spec bearing shell designed for fracture-split (fractured-cap) connecting rods in modern Cummins diesel engines . This bearing is a direct replacement for OE part number 3945918 , providing precise fitment and restored oil clearance after crankshaft journal reconditioning. Fractured-cap connecting rods require extremely tight bearing tolerances due to their unique cracked mating surfaces. The 0.25 mm undersize specification compensates for light crankshaft regrinding, ensuring proper bearing crush, stable oil film thickness, and accurate journal alignment under high combustion loads. Manufactured using premium bearing alloys with advanced overlay technology, the RB-3945918 bearing offers excellent load-carrying capacity, fatigue resistance, and protection against metal-to-metal contact. Precision shell geometry promotes even load distribution, reduced friction, and extended crankshaft life in high-output diesel applications. This bearing is commonly installed during engine rebuilds, bottom-end overhauls, crankshaft machining repairs, and professional remanufacturing projects . It is trusted by diesel technicians and engine builders who require OEM-level accuracy and durability for fractured-cap rod applications. Cross-Reference & Fitment Aftermarket Reference: RB-3945918 OEM Reference: 3945918 Size: 0.25 mm Undersize Type: Fractured-Cap Connecting Rod Bearing Fitment Note: Use only with crankshafts ground 0.25 mm undersize