I’m curious on what you guys would recommend on a newly acquired 01 ram 2500. I don’t know what has been run previously. But I’m wondering what is regarded as the best HDEO’s in the current market. It seems delo, valvoline, rotella, and delvac have all had their following over the years but which has stood the test of time? I live in NY so we do see cold temps during the winter. I was thinking of something that has a 5w40 variant for winter and a 15w40 variant for summer. But what do you guys think.