Hey all I am just about to purchase a 6.0 powerstroke but I have a few questions. I've done a ton of research on this engine before I go ahead with the purchase. The truck is bulletproofed and has all the work done to it but I am curious what oil would be best to run. I've put down the options to Valvoline Premium Blue 5w40, Schaeffer's 9000 5w40, Amsoil 5w40, Delvac 1 5w40, Delo 5w40, and Rotella T6. I also heard good things about the Archoil additive as well. I want to put whatever oil will make my truck run the best especially in the cold. I will use the motorcraft OEM oil filters. Thanks for all the help!