Development of Long Life Engine Oil Using Substituent Additive for ZnDTP
Engine oil combined with SPZn instead of ZnDTP shows excellent total base number (TBN) retention in oxidation and NOx gas bubbling tests. The wear resistance of engine oil combined with SPZn was similar to oil combined with ZnDTP in a four-ball test. Prototype engine oils with 1.0 wt% of sulfated ash and 0.04wt%-0.09wt% of SPZn-derived phosphorus were prepared and a JASO valve train wear test was performed on them. The wear resistance of engine oil including SPZn with P = 0.09 wt% was greater than that of engine oil including ZnDTP. This result shows the possibility of reduce the phosphorus in engine oil by using SPZn.