Quote:
He said industry will also need to take into account the fuel economy that vehicles achieve after oil is installed in an engine – not just the score that fresh oil achieves on an engine test. As oil ages in an engine, fuel economy decreases. Friction modifiers and other chemistries are depleted, the oil thickens due to oxidation and accumulation of soot.
Formulation can delay this decrease in performance, McCabe said, but only so much. To sustain fuel economy improvements, drain intervals may need to be shortened.
“As fuel economy deteriorates over time, there comes a point when swapping an old oil for a new one becomes the best approach to better fuel economy,” he said. “It is hard to say what the optimum point is, as it varies by engine and cycle. But the overall trend is there: The longer a drain interval, the more fuel economy will deteriorate.”
http://www.imakenews.com/lng/e_article001579661.cfm?x=bgct1JL,blqdw92
He said industry will also need to take into account the fuel economy that vehicles achieve after oil is installed in an engine – not just the score that fresh oil achieves on an engine test. As oil ages in an engine, fuel economy decreases. Friction modifiers and other chemistries are depleted, the oil thickens due to oxidation and accumulation of soot.
Formulation can delay this decrease in performance, McCabe said, but only so much. To sustain fuel economy improvements, drain intervals may need to be shortened.
“As fuel economy deteriorates over time, there comes a point when swapping an old oil for a new one becomes the best approach to better fuel economy,” he said. “It is hard to say what the optimum point is, as it varies by engine and cycle. But the overall trend is there: The longer a drain interval, the more fuel economy will deteriorate.”
http://www.imakenews.com/lng/e_article001579661.cfm?x=bgct1JL,blqdw92