Long periods I would not go much above 12-1250.
Short bursts dont worry to much about, wont have time to heat soak.
Either way let the EGT's cool off prior to turning the truck off.
I have stock studs in my truck and tow a lot with it.
I think most of the puking in these trucks are caused from the Oil Cooler Clogged or the EGR cooler boiling the coolant.
If you keep the coolant below the min. line while the truck is hot, keep the coolant clean, and can beat on the truck a little without it puking then I doubt you will have a problem.