Seriously, I'd run that oil till the car tells you to change it. There's a book called "The 3,000 mile lie" that states, IIRC, that you don't need to change you oil, just the filter. With Mobil being synthetic it doesn't breakdown like dino oil does. Right now I'm only changing the filter in my wife's 04' Ranier and have gone about 13K or so w/o changing the oil. I'm also doing this in my beater car, 93' Regal that has 117K on the clock. When it comes time to change the oil in the Crossfire I'm going to go out and get that Mobil 1 extended life (15K) and try that out. If you look at your oil when it has over 6K on it there's still a golden color to it, although not like new, but its really not that bad. So, what to you guys think about my idea/theory. For the record, I drive about 11.5 miles to work and its less then a mile on and less than a mile off of the freeway. I also have taken trips to WV and Chicago this year and plan on the Dragon Run down to Tenn./North Carolina in about 2 weeks, so I do alot of freeway driving anyway!