moving cross country (north to south)

Im moving back to FL from Chicago and am going to pull a uhaul. Are there any things i need to pay special attention for this move with the range. I know i will have to get the trailer harness, but do i need a 7 or 4 pin? i have 78K miles on it (did 75K service at 72K) and dont want to get stuck. Ive never driven it for more than 3 hrs due to the past issues but shes been running great now and after the many rips to the stealership.

Just checking to see if there is anything ill need to look out for while im pulling the trailer.
Any other fluids i should change, belts, plugs anything

thanks in advance