I finally made the transition to the dark side and I couldn't be happier. I've been driving a 7.3 for a while but I just got an '06 5.9 24v with a G56. In the 7.3 I just ran Delvac and the tractor seems happy with it as well. Is the Cummins happy with Delvac? Walmart also sells a Mopar oil filter... is that fine?