Thanks for your post, this is the type of information I am looking for.
First off welcome to the org.
Here is what I would recommend in your situation. I would change the oil and use a 5w40 weight oil. I strongly suggest that you invest in a bypass oil filter because idling so much is going to put more than the average amount of soot in the oil.
Never heard of a bypass oil filter. I will investigate it
Do the high idle mod and use it. Just idling even with a 300 rpm variance isn't going to keep enough heat in the cylinders to prevent stacking. Have your FICM updated with the latest flash from PHP. That has a turbo vane exercise routine when idling to keep the turbo vanes from sooting up and getting stuck without the drawbacks of the latest Ford flash.
I am probably too conservative on the high idle range. I will have somebody sit in the cab while idling and then try the fast idle. I think idle is around 600 rpm and I think it will idle up to at least 1500 rpm but I'm never in the cab when it idles up so I really don't know.
"FICM updated with the lastest flash from PHP"- Gonna have to look this one up, don't know what either stand for but I will shortly. Gotta get these acronyms down
What are the drawbacks of the latest Ford Flash?
Delete the EGR with the kit of your choice. I like the Sinister kit. Make sure you get that Edge Insight as soon as you can. You have to monitor ECT and EOT. That is what will tell you if your oil cooler is clogging up. Flush the cooling system and replace the coolant with CAT EC-1 rated ELC coolant. And finally, getting an SCT X3 and putting a conservative tune on it could make it perform better and last longer than retaining the stock tuning.
Also you might find this helpful. Things to consider about owning a 6.0L
What advantage do I get in going non-stock tuning? Forgive me if I seem too conservative but I have always viewed diesels from a workman's standpoint, not performance. I need it to be able to get from point A to point B, power the PTO for a few hours a day, and be reliable and long lasting.
If a re-program can increase longevity I would like to know why. I am actually pretty pleased with the stock performance, I'm about 100 HP more than our old 7.3 PSD, which I thought had plenty of power.
Thanks for all your replies, I look forward to gaining and sharing as much knowledge as I can.