Does oil brand really matter? What do you say to a guy with a 1995 Buick LeSabre 3800 that has over 300,000 ml with 5,000 ml changes on Valvoline 10W30 Dino and Cheapo Filter from the local Quick Change. You need better oil and filter or shorter intervals? I'm sure there are better oil, filters, and the change interval might be borderline to long with that oil but why mess with success. The car uses 1 QT of oil every 3000 ml. Personally its enough to make me consider the Wally World $17.95 oil change for our own 1995 LeSabre!