A New Generation of Multigrade “MS” Oils: Laboratory and Field Performance

This paper characterizes the features and describes some of the benefits of the present generation of multigrade “MS” oils. Particular emphasis is placed upon viscosity retention characteristics as a function of the stability of the viscosity index improver.

Comparative automobile field tests in private commuter, taxicab, and highway service are shown for both SAE 10W-30 and a carefully compounded SAE 10W-40 oil. Observations of cylinder and piston ring wear, crankcase deposits, PCV valve cleanliness, and oil economy are reported.