2000 Excursion, 7.3 Power Stroke Diesel.
2000 F150 , 5.4 Triton
Is it harmful for either of these trucks to idle (Air Conditioning ON) ALL night ?

Will there be enough oil delivery to the top at idle?
Overheating issues?

A friend (and maybe I) will be going to help with the hurricane cleanup
and may need to sleep in the truck with the AC running.

 

I've spent years in the "big rigs" and have let my engine run all night because I needed either air conditioning or heat. At a dead idle, most engines will not lube properly. Upper cylinder areas don't get oiled correctly as they rely on sling from rod bearings. Many engines won't lube the front cam gears and/or timing chains properly. Other factors come into play, such as too low a combustion temp producing contaminates. Stepping up the idle to (for my big rig) 1000 rpm when I had to let it run eliminated most of those problems. Understand though, the engine IS running and it WILL incur wear. Then again, that's what they're for. Most big rigs will allow the use of the cruise control while parked boost rpm to acceptable levels. Don't know if you can do that with yours.

Change the oil at more frequent intervals, and understand the hit in mileage numbers. Don't let it stay at dead idle if you can avoid it. Good luck, you're to be admired for helping those down there in NO.

Flagship

 

This may help for the diesel.
http://www.thedieselstop.com/content...%2F%2415%20AIC

I doubt it will be a good thing for either engine, but I don't think there will be any catastrophic failures in either case.