Ken - I have noticed that fuelefficiency has dropped from 23 hwy to about 20-21 hwy. Could it be related to the oil issue, or is it more likely a switch from summer blend to cool season gas - which should have occured around the same time?

 

Sorry, I don't live in an area where the blends (knowingly) change from one season to the next. If you typically experience a drop in milage from this blend change, then it is most likely that. I would keep track of the oil consumption between changes.