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Q: Is it okay to add conventional motor oil to synthetic oil in the car already?

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I have some synthetic oil in the reservoir already but I can't find any in stores to top off. Is it ok to add conventional oil or will this damage the vehicle?

My car has 130000 miles.
My car has an automatic transmission.

Hi there. Mixing oils of conventional and synthetic types will not cause any problems at all as long as you are using the correct weight oils for the engine. Mixing the oil is better than running the engine low on oil. Just remember that you should get the oil and filter changed as if you used regular conventional oil until you have all synthetic oil again.

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