King Engine Bearings MB5503AM030 AM-Series Main Bearing Set .030 Undersize Ford V8 351ci 5.8L

The King Engine Bearings MB5503AM030 is a complete crankshaft main bearing set engineered for Ford V8 351ci (5.8L) 16-valve engines. This is the .030-inch (0.75mm) undersize version, designed for use with reground or turned crankshafts that have been machined to .030-inch undersize on the main journals.

Part of King's AM-Series lineup, these bearings use a bi-metal aluminum-based construction — King's softest and most conformable bearing material — making them an excellent OE-replacement choice for street and marine engine rebuilds operating under low to moderate load conditions.

Key Features:

• Bi-Metal Construction: Aluminum-copper-tin alloy bonded to a high-strength steel backing for reliable OE-spec performance
• Superior Embeddability: Aluminum base material allows small particles to embed harmlessly, protecting crankshaft journals from scratching and reducing wear on the Babbitt overlay
• Precision Tolerance Control: Manufactured to within ±.0001-inch for consistent oil clearance and reliable crank seating
• Lead-Free Formula: Environmentally responsible, user-safe bearing material with no lead content
• 3/4 Groove Design: Optimized oil distribution across main bearing surfaces
• Complete Set: Includes 5 pairs of main bearing shells to cover all main journals
• Crankshaft Undersize: .030-inch (.75mm) undersize — matches cranks ground to .030 under standard

King Engine Bearings has specialized exclusively in engine bearings since 1960, supplying the automotive, marine, aviation, and heavy-duty truck markets worldwide. The AM-Series is recommended for OE replacement and standard street/marine rebuilds where the original crankshaft geometry and load parameters are maintained.