Hex Head Bolt 5/16-18 x 1-1/2 Grade 5 10pk

The Hex Head Bolt 5/16-18 x 1-1/2 Grade 5 10pk by ALLSTAR PERFORMANCE is a professional-grade fastener engineered for high-stress automotive applications where reliability cannot be compromised. Whether you're assembling engine blocks, securing suspension components, or fastening transmission housings, these bolts deliver the tensile strength and consistency demanded by serious mechanics and performance builders. Grade 5 specification ensures these bolts withstand the vibration, thermal cycling, and mechanical loads inherent in modern engine bays and drivetrain systems.

Grade 5 hex head bolts feature a minimum tensile strength of 120,000 PSI, making them suitable for critical fastening where standard hardware would fail under load. The 5/16-inch diameter with 18 threads-per-inch (UNC) pitch provides optimal grip and clamping force without over-stressing aluminum or cast iron components common in automotive construction. The 1-1/2 inch length accommodates typical engine bay spacing, mounting plates, and structural brackets found in both OEM and aftermarket installations. Heat-treated steel construction resists corrosion and maintains integrity through repeated thermal expansion cycles—essential when dealing with engine compartment temperatures and outdoor storage conditions.

This 10-pack is ideal for engine rebuilds, carbureted or fuel-injected engine conversions, and performance modifications where original fasteners require replacement. Mechanics and fabricators trust ALLSTAR PERFORMANCE bolts for head gasket installation, intake manifold assembly, water pump mounting, and alternator bracket attachment. The quantity and specification make this pack a cost-effective solution for those building or restoring multiple vehicles, or for shops maintaining an organized fastener inventory. Proper torque application—typically 25-30 ft-lbs for this size in aluminum—ensures maximum clamping load and leak-free seals in critical engine applications.