Observations Through a Transparent Oil Pan During Cold-Start, Short-Trip Service

Cold-start, short-trip driving causes the accumulation of fuel, water, and other contaminants in oil. In this type of service the engine oil degrades at a rapid rate. To gain a better understanding of the degradation, the oil under these conditions was observed and photographed through a transparent oil pan. In addition the oil was analyzed to provide a quantitative measure of the degradation. Oil analysis results confirmed what was observed visually; once oil became warmer, sludge and contaminants were removed, and many of the oil's properties (acid number, pentane insolubles, water in oil, etc.) improved.