I have a 6.0 thats runs awesome unloaded. When pulling something heavy on a hot day itll shut off. Like if something is getting to hot. If I crank it once its shut off it will not turn on. yet if I wait about 5 minutes and let her cool she ll crank right up. if I let her run a few miles down the road I ll get the same result. It seems to me shes getting to hot...and shutting herself down until it cools to a minimal temp?! any feedback?!

 

Sounds like HPOP system leak, either HPOP, STC fitting, o-rings for dummy plugs and standpipes.

Do you have a way to monitor vitals like ICP, IPR, EOT,ECT, IAT 1&2, TFT.

 

What year is the truck? and any mods to it??

 

its 05 350 only got a sct programmer and intake thats it. The truck runs awesome unloaded but I live in south texas where its hot as hell. if im pulling something on a hot day it ll shut off. But I had one incident where I was pulling some round bales...once I reached my destination while I was unloading the bales. I let her idle and she started chuggin like if It was in a lope. Like I said unloaded she s runs beautifully even on a scorching day.

 

Does the fan kick on? pretty easy to hear if it does. is your egr valve at least plugged in even if te cooler is deleted? It very well could be a high pressure oil leak, 05s are notorious for the STC fitting failing, it eventually gets worse and worse till you have to wait a half hour for it to restart. If planning to repace stc fitting then also plan on replacing dummy plugs and stand pipes, Tousley Ford sells the stand pipe and dummy plug kit for $102 and STC fitting for $38.

 

No usually I never hear the fan kick on...it ll be pulling good but all of sudden it ll shut off outta no where. whats STC abbreviated for by the way ?

 

STC fitting, Snap To Connect fitting on high pressure oil pump, it is fitting made by Aeroquip that Ford/International uses on the pump for easy assembly but it is used in the wrong way and can flex so it can and will fail over time, the new fitting is solid so it can't flex.
stc fitting - Bing Images
stc fitting - Bing Images
top is the old style, bottom is the one piece new style.