The ability of a lubricant to reduce scuffing, scoring and seizure that can occur when highly-loaded moving surfaces are in contact. High loads are applied to moving surfaces that are in contact. Commonly used laboratory test measurements of the EP level of greases are the Timken OK Load (ASTM D2509, 4-Ball Weld and Load Wear Index (ASTM D2596), and EP by SRV Step Load (ASTM D5706).