Many of the major oil companies make special synthetic diesel oil that has increased detergent and wear properties over oils manufactured for gasoline powered engines. This is because diesel engines produce more internal soot and components of sludge due to their higher heat than gasoline engines. If you had synthetic oil put in at your last oil change and you notice your oil level is low, you can use a mineral based oil of the same viscosity as a stop gap for a short period of time. With the new formulations in synthetic oils, an engine will “become accustomed to” synthetic oil or a mineral oil, and using different type of oil for lengthy periods of time can cause internal problems.
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