I usually put 12-15k miles per year and change the oil in March and November, so that comes out to 6-8k miles per oci. This year though I have put only around 4k miles since last time oil was changed in March at 213k miles. Vehicle is 1997 MB E320 (L6), oil is Mobil1 10w40 HM (7qts) and filter is Mann. Most of the trips are between 3-10 miles with 25-45mph driving, but I step it up to 80mph quite often on the highway. The oil gets to full operational temperature every day. I will put between 2-3k miles between now and next March. Do you guys think I should change the oil before the winter hits, or wait til next March? By the way this engine is pretty easy on the oil, doesn't burn a drop between oci's and also it is pretty clean inside.