Donnyj08 is right on with his assessment. Any solid 5w30 API SN ILSAC GF-5 will do well given right change interval. I think that Valvoline Synpower, Mobil Super Synthetic, Castrol Edge black bottle, Pennzoil Platinum 5w30 would be good for 7500 miles. Castrol w titanium gold bottle, Mobil 1 EP, and Pennzoil Ultra could go longer obviously up to 15k. In order to try that it would be advisable to get a UOA done at 10k miles to assess the life left in the oil.