has any one when from dino oil to full synthetic oil & had better m p g & what oil & how much better m p g did you get ? i have 2011 chevy 2500 Duramax pulling 35 ft 5th wheel..
I am mixed up. When somebody is happy with their brand of oil or vehicle why do others want to make them change anything. I might change my thinking but it will be doing it not others. chevman getting old ya think?