I experienced nearly the same thing you are experiencing in a Uhaul truck a few years back.
I was volunteered by the DW to move her nephew to college in Wyoming.
We had an 1995 ford f-350 box truck and was towing a car on dolly.the truck ran fine for several hours the first night ,but during daylight hours and 100 degree temps the problem started.
The Uhaul did exactly as you described ,lost power, started surging and then shut down leaving us stranded on interstate.We called Uhaul ,they dispatched a tow and took us to a repair center.the mechanic replaced every electrical component (except fuel pump)on truck.
Thinking problem was resolved we resumed our journey,a few hours later we were once again broken down sitting by interstate.
To make a long story short {I suspected vapor lock problems}I quickly discovered that by stopping and filling tank (about 75 mile intervals )with cool gas from underground tanks the problem went away.
Trying to finish the trip I neglected to stop and refuel like I had been doing and sure enough truck quit about 60 miles from our destination.I let it cool ,refired and completed trip.
While engine temps were reading normal,the underhood temps can be very hot causing the gas to basically boil in the lines.
Finally got the heap to Laramie and left it there for someone else
to deal with
