Engine Main & Connecting Rod Bearing Set +0.50mm BMW 340i 440i 540i X5 X6 B58

This high-performance bearing set is designed for BMW B58 and S58 engines where the crankshaft journals have been machined to a +0.50mm undersize. When an engine experiences significant journal wear or scoring, professional grinding is required to restore a perfect circular profile; these oversized bearings compensate for that material removal to achieve factory-spec oil clearances. This kit includes both main and connecting rod bearings, providing a complete bottom-end solution. Engineered with advanced multi-layer materials, they offer exceptional load-carrying capacity and fatigue resistance, essential for the high-boost environments of BMW’s turbocharged straight-six engines. Replacing both sets during a rebuild ensures uniform oil pressure and long-term rotational stability.