Why is the oil in my car darker than usual?

–George Kennedy/Boldride

I switched to synthetic oil, but now my oil looks darker than usual. Should I use a specific brand, or am I not getting what I paid for?

Q. I recently had the oil changed to synthetic in my Subaru WRX, but now the oil looks darker than the last time it was changed. I have the oil changed regularly, but this time it looks different. Should I use a specific brand, or am I not getting what I paid for?

A. Different brands of oil can look different, but they generally perform the same. Over the years, I have used Mobil, Castrol, Royal Purple, and even Walmart oil. Some oils are darker than others due to the base stocks they are blended with during production. In my non-scientific opinion, I would say that the oils that I have used under normal driving conditions all perform fine, so I tend to shop for price. Another reason your oil could be darker is if the old dirty oil didn’t fully drain from the engine. You could have the oil analyzed, but that would cost as much as just changing the oil, so I suggest supplying your own oil when it’s getting changed the next time. Also, building a trusting relationship with the shop that services your vehicles can eliminate a lot of the questions and stress.


John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE certified master technician. Email your car question to jpaul@aaanortheast.com.