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Q: I accidentally got synthetic oil instead of regular motor oil and only put in quart and a half. Will it mess up my engine?

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I accidentally put synthetic oil in my truck instead of regular. I was about a quart and half in before I noticed. Will it damage my truck if I put the rest in?

My car has 158000 miles.
My car has an automatic transmission.

A: Hi there. Today’s synthetic oils are much d...

Hi there. Today’s synthetic oils are much different than in years past, so accidental mixing like you’ve described is not as damaging to the engine as in years past. However, I would recommend having the oil changed sooner rather than later so that the oil is consistent and your internal engine components are properly lubricated. Since you’ve added a quart and a half, that raises a red flag to me that you may have some type of oiling issues that should be checked out soon. With winter coming soon, it’s probably a good idea to change your oil anyways to the recommended blend and weight.

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