King Engine Bearings MB 551AM0.5 Main Bearing Set Toyota 3K 4K +0.50mm Oversize

The King Engine Bearings MB 551AM0.5 is a crankshaft main bearing set engineered for Toyota 3K and 4K engines. This set is machined to a +0.50mm oversize specification, making it the correct choice for engines with reground or worn crankshafts requiring an oversized bearing fit.

This bearing set uses King's AM-Series bi-metal aluminum construction, featuring a 100% lead-free aluminum alloy equivalent to SAE-783. The AM-Series material is specifically formulated for low and medium load engines, making it well suited for street and marine rebuild applications.

Key Features:

• AM-Series Bi-Metal Construction: Lead-free aluminum alloy equivalent to SAE-783, ideal for low and medium load engines
• +0.50mm Oversize: Designed for use with reground crankshafts machined to the 0.50mm undersize specification
• Superior Embeddability: Provides greater tolerance for macro-particle contamination, helping reduce scratching of crank journals
• Bull's Eye Tolerance™ Technology: King's proprietary production process combining precision machining, overplating, and computerized wall thickness monitoring for consistent dimensional accuracy
• 100% Lead-Free: Environmentally responsible and user-safe formulation
• Tight Tolerance Control: Precision manufactured to ±0.0001 inch for proper oil clearance and fitment

King Engine Bearings has specialized exclusively in engine bearings since 1960, producing a comprehensive range of bearings for automotive, light and heavy-duty truck, marine, aviation, and standby power applications. Every King bearing is engineered and manufactured under one roof to ensure consistent quality from raw material to finished product.