I am another advocate with bswombaugh here..
Again, it doesnt matter how long the oil will last as how much dirt and crap is floating around because the oil filter is totally full of it...
Yes, you can run your synthetics/etc., oils till the cows come in, but you are wearing out your engine parts way, way, faster than they would be worn with clean oil...
It's as simple as that...
Example - BMW for years, used to bring in all their vehicles for a complete oil change of the engine, transmission, and differential, at 1,200 miles !
Why ? Because the oil was full of things that needed to be removed in order to insure longevity of the engine, transmission, and rear end parts..
Then, they changed this requirement to the M cars only... Because it was costing them so much money...
Then, because the bean counters got involved, they started offering free oil changes for X number of years, but the oil changes were spaced out way too far (in my opinion), in order to get people to think that owning a Bimmer is a not so expensive experience...
So, in the end, when ever I will buy another BMW ( and I will), I will be looking closely at the oil change, transmission and differential oil change, brake fluid change, etc., and if its on those way too long intervals, Im walking away...
There is just too much wear internally for my needs...
Others who regularly lease/trade/etc., vehicles are not bothered by the long intervals they run their cars into, because, well, they are getting rid of it anyway.. Tsk tsk tsk...
I would rather buy dozens of Jeep Dealership oil changes at $30 at 2-3k miles, than run anyone's synthetic oil for more miles ever...
My 2009 Grand Cherokee with the 5/7L Hemi has had 13 oil changes and its just turning 24k miles... Yeah, to me the $390 spent on a new oil, filter, tire rotation, inspection, is way worth it.. Your experience/opinion/mileage may differ !
Dan F