Walmart Oil Changes

We had gotten into the habit of getting our oil changed at Walmart. They are easy to find, and we can do other shopping while we wait.

But while we were in Oregon, we found that the Walmarts no longer do oil changes, apparently in the entire state. We went to Jiffy Lube instead. Our gas mileage improved by 2mpg, back to where it was the last time we used Jiffylube (it had been slowly declining since that visit).


Wherever we get our service done, we always use full synthetic oil, so it is difficult for us to fathom the difference. But it makes us wonder if this has any bearing on the service being withdrawn in OR?