Q: adding oil to full synthetic

asked by on October 25, 2016

i went for some repairs and rhe auto shop put in full synthdtic oil. I need to add a quart of oil, as it is a quart low. Is it ok to mix regular Penzoil to the full synthetic that is in there now?

Hello. There is no problem with you adding a conventional oil to your vehicle if it already has synthetic in it. The only thing that you need to make sure of is that you are using the correct weight oil in your car. If you are consistently losing oil that is something that you are going to want to have checked out.

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