Why does Exxon Elite turn dark very early in the drain interval?
ExxonMobil: Because of the wide variety of additives used in a modern engine oil like Aviation Oil Elite 20W-50 and the manner in which these additives behave in your engine, oil color is not a very reliable way to determine oil quality. As you may already know, impurities are created in your engine as a by-product of combustion. Aviation Oil Elite 20W-50 is formulated with a very robust dispersant to uniformly suspend these impurities throughout the oil so that they are removed from the engine when the old oil is drained. Sometimes these suspended impurities cause the used oil to appear darker than other oils. This is a sign that Elite is doing its job to keep your engine clean.
