Full tune-up, brake check, and lube everything.
If you are confident that the truck alone will make it, the trailer isn't going to change that. It will rob you of speed and power, but since you say you are going to take it easy... You will take a considerable hit on gas mileage, and will get worse, the faster you go while dragging the parachute (enclosed trailer).
Sounds like you are getting a (nearly) free vacation!