for those who said car is good for 7K without oil change....
have you "actually" went to see inside the engine... Not engine oil .. Engine.
Tell me how it looks like....
It all depends on what kinda car you're talking about..... but I do my oil change Max 3,000 miles no matter what. oil changes also saves your gas mileage as well. I'm sticking my way. You also know why one of the reason ppl's spark plugs gets messed up as well? Good Oils helps to lessen the Friction from piston wall to the other side of the wall. (will help avoid from overheating)