From time to time members ask "should I change my oil now or wait until after my long trip" when they are nearing the end of an OCI. I am facing the same dilemma now as I will have 4K to 4.5K on the dino in my Corolla when I leave on a 1500 to 2K mile trip.
I normally change at 5K but I've decided to extend the interval until after the trip with a few adjustments. I'm going to drain a quart and add a fresh quart before the trip to replentish additives. I'm basing this decision on the data gathered on this site...notably the '3 Mad Ponchos' study which showed that adding a quart of oil significantly improved the oil in the pan...and also the theory that used oil lubricates better than fresh oil (until the point that it begins to break down).
PS: the current oil has about 80% highway miles..
What are your thoughts on my theory?
I normally change at 5K but I've decided to extend the interval until after the trip with a few adjustments. I'm going to drain a quart and add a fresh quart before the trip to replentish additives. I'm basing this decision on the data gathered on this site...notably the '3 Mad Ponchos' study which showed that adding a quart of oil significantly improved the oil in the pan...and also the theory that used oil lubricates better than fresh oil (until the point that it begins to break down).
PS: the current oil has about 80% highway miles..
What are your thoughts on my theory?