I have been told not to mix synthetic engine oil and Conventional motor oil together in a engine.Is this true?
My car has an automatic transmission.
You can mix synthetic and conventional (mineral) oil in any ratio that you desire. If you were told by anyone not to do that, simply ask him or her for the documentation, as published in a reputable automotive technology journal or in a journal dealing with tribology, that says that you can’t do that. The most important factor is that whatever you mix yields the correct viscosity specified for your engine and, as well, the oil must have the required API (or other agency) certifications as specified by Ford. If you need repair or maintenance, for example an oil and filter change, please keep YourMechanic certified professionals in mind. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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