King Engine Bearings CR4059SI0.5 SI-Series Connecting Rod Bearing Set Oversize - 0.50mm

The King Engine Bearings CR4059SI0.5 is a +0.50mm oversize connecting rod bearing set engineered for General Motors 138ci 2.3L engines, including the L40 and LD2 16-valve applications. Part of King's SI-Series line, these bearings are the ideal choice for engine rebuilds involving nodular cast iron crankshafts that have been reground to the +0.50mm undersize specification.

Material & Construction:

• Bi-Metal Silicon Aluminum construction — an aluminum-based alloy strengthened with 2.5–3% silicon content
• Designed for medium-load engine applications and nodular cast iron crankshafts
• Improved surface finish reduces microscopic ferrite peaks on reground or repolished crankshaft journals

SI-Series Features:

• Optimized oil clearance reduces wear and extends engine service life
• Precision wall thickness tolerances ensure consistent press fit and bearing stability
• Reduced operating noise and vibration compared to worn or out-of-spec bearings
• Direct OE-replacement fitment — no modification required
• Suitable for aftermarket gasoline engine rebuilding and performance engines with stock crankshafts

King Engine Bearings has been a trusted name in precision engine bearings since 1960, supplying high-quality bearings for automotive, light and heavy-duty truck, marine, aviation, and standby power applications. Every SI-Series bearing is manufactured to exacting tolerances to deliver reliable performance and long engine life.