FYI: I work on cars for a living. About 50% of my business is oil changes. Many customers go between 4k and 5k miles untill they change the engine oil. I've seen mobil one with good fram filters after 4k and it looks like regular crap oil with a generic filter. While synthetic oil is better in terms of its heat resistance properties and its ability to run clean at extended intervails (3500 to 4000 mi MAX) you still should change your oil every 3 months or 3,000 miles which ever comes first.
I mean think about it. Lets take regular ol' valvoline 5w30. This oil has gone pretty much unchanged for quite some time. Now lets take a regular 3387A fram sure grip oil filter. Again unchanged for quite some time.
Now lets say we are going to change the oil on a Pontiac 1998 Grand Prix
3.8L. Again using scenerio's in which the objects invovled have gone virtually without change for quite some time.Now suppose when you bought your grand prix back in '98 the book and the dealer said change the oil every 3mths or 3k mi. Back in '98 that was the norm. People were satisfied with that standard. But as time rolled by and people lives became more automated, we got lazy. Now to get to the point: you just bought an '04 pontiac grand prix 3.8l. You got your reg. val
10w30 with your fram sure grip. Do you really believe all things considered that you can safely push that oil and filter 5 mths 5,000 miles and the owners manuals suggest and get the full life out of that motor? even if you bought mobil 1 15k or whatever they claim it to be, you are still using plain jane paper filters. Who cares what they put on the box. A oil filter is paper wrapped in metal. theres know such thing as a 10k paper oil filter--trust me.Lets try to get back to atleast making time to doing one thing we might not want to do. I'm sure if your car broke down due to oil failure or some type of engine oil neglect, mobil wouldnt say ok here's a new motor.
Changing the oil every 3mo or 3k miles is the single most important preventitive maintence service that should be executed without question.
but like I said FYI: