At this point I'm happy I don't have an AUX or any other thing that is tied into the truck's main A/C system. Holy CR#@, the system is complex enough, without adding another little system on to it. As a newcomer to the art of refigeration, and mind you all it's as much art as science, I have no problems understanding why these auxilliary climate control lawnmowers develop problems quickly. If the system is tied into the climate control of the truck itself, the problem can be anywhere, not just in the AUX. The teeniest-tiniest pinhole leak in any A/C system will keep it form staying properly charged and working right, and when you complicate that which is already complicated, you could be struggling all summer long to get functioning A/C.
-Weave-
...Maybe I'll duct an old reefer from my box to chill the thing down in the western and southern heat...