I had a 1988 ranger that I changed the oil between 5,000miles and 10,000miles.I gave it away at 384,000 miles(I used it for work and my wife convinced me that I shouldn't trust it any more) and it still only burned 1 to 2 quarts between oil changes.The oils and engine construction have become so good that you don't really need to worry about it.I am old enough that I can remember when if you changed your oil religiously and treated it nice most engines were worn out at 100,000 miles.There are even a few manufactures that now have oil change intervals as long as 8,000 miles. In the last 30 years I have not had a oil related problem but in the 60s and 70s that was a whole different story.The older cars that I have had that made it to the mid to late 80s without many miles will hit 250,000 to 300,000 miles with out burning excess oil or make the normal worn out noises.Sorry for being so long winded but as stated before unless you are racing or some other extreme use I don't think that you need to change it that often(unless you use it in a waste oil heater in your garage-ha-ha).