We have a 40' fifth wheel and before that was a 32' TT. And we found it hard with the travel trailer to find good places to stop so we went to transfer flow and bought a 40 gallon external automatic fuel tank.
With the TT we could go almost 700 miles without stopping and at that range we could pick our stations.
With the fifth wheel not as far but still could pick and choose our stations.
We just got a new truck and we are doing the same installing a 50 gallon tank.
This way we pretty much can make our destination set up and then take just the tow vehicle in and fill up.