Schaeffers SynShield Ultra Performance 10w30 Oil is a premium advanced performance, synthetic plus, heavy-duty diesel engine oil formulated to provide maximum protection against wear, oxidation, deposit formation, soot contamination and aeration. SynShield Ultra Performance 10w30 is built for on-highway and off-highway applications that are subjected to severe stop-and-go, excessive idling, short haul and/or severe duty operating conditions. Using Schaeffer's proprietary friction modifiers, Micron Moly and Penetro, SynShield Ultra Performance 10w30 creates a slippery, tenacious shield that prevents metal-to-metal contact. This added layer of durability protection significantly reduces wear on bearings, rings, pistons, cylinders and valve trains SynShield Ultra Performance 10w30 Engine Oil is suitable for use in 2007 and 2010 emission complaint engines that utilize heavy exhaust gas recirculation (EGR) and exhaust after-treatment devices such as diesel particulate filters (DPFs) with or without diesel oxidation catalysts (DOCs) and selective catalytic reduction (SCR). Schaeffer's 10w30 diesel oil meets and exceeds API CK-4 specifications.