Originally Posted by sharpaye7
I suppose that's true. But am i right in saying that the main reason people are doing it is so the warranty doesn't get void?
That would be a reason, however the service intervals are set for a reason & very little customers can do to argue. Not following the mfctrs specified service schedule would defo invalidate your warranty.
Saying that, i have always been a firm believer that no oils are good enough to safely last 15-20K miles, so i've usually as a minimum changed the oils in my cars every 5-6K miles.