Hi, all. I'd like to hear some advices regarding extended OCI for my car. First, about my car and my driving habits: 1. What kind of vehicle you have 2005 4runner v8 4.7L 4wd 35k miles. 2. What your owner's manual says -- not just viscosity, but certifications (look for acronyms like API SM, ILSAC GF-4, etc.) and change intervals as well SM 5w30 5000m or 6 mon which comes first 3. Where you live New York city 4. How you drive (easy? hard? fast? slow?) Usually slow and easy 5. What your daily drive is like (short trips? long trips? city? highway?) Local short trips <1 mile. 6. Whether your car has any known problems No. I only drove my 4runner something like 2000 miles per year, with 2 short trips around 1 mile a day, and a 40 miles trip once a month. Usually I do the oil change at dealership every 6 months or 1000 miles. I began to seriously think to extend OCI when I lately suspected that occasionally the dealership didn't change the oil or filter at all. Maybe I just wasted time and money to do oil change every 6 months in my case. My question is if I can switch to Mobile 1 synthetic and safely extend OCI to 1 year/2k miles? Thanks in advance!