just good quality oil with regular changes is all you need on the 7.3 and the rest. I actually had a bypass filter on my 7.3 and did oil analysis to see when it had to be changed, I did filters every 15000miles and complete oil change every second filter change and everything was with in spec.
Hmmm, we have dualing opinions on Archoil or Snake oil, depending which side of the isle you stand. Whether or not Secret Sauces work can be debated. I'm not one of the faithful, but I did give it a try. No love for me and I will be taking the engine apart shortly. Need to build an elevated walk around the front of the truck for easier access to the engine.
Let the fun begin!
sorry I thought it said Amsoil not Archoil haha. Archoil is one of the few diesel additives I use and believe work well. it may work for you to get that one going but I don't know, what I was intending in the other post is good quality oil (rotella t6 is all I used in my 7.3 and my 6.7) and regular oil changes is what those engines need or they can have some issues. now if some one didn't do that because believe it or not most don't, then you have to figure out ways to get it working again.
