What brand of oil you guys use on your 6.7 Cummins? I know its a special low sulfur oil that they carry, but do we really have to use the "Mopar" brand? The dealer said it's ok to do it on your own, but suggested to only use their brand. But its $25 a gallon and that's ridiculous. So what oil brand you guys use other than the factory thats safe and good quality for our 6.7's? Thanks, Joseph.

In Europe the best oil, especially for engines use on track day (you are on a post dedicated to this) is the genrally the Motul type. But I tell you, 25 box for a gallon, is chip, the Motul are more in the range of 25€ the 2 liters, thats 55$ per gallon