Probably the pump
I had the same problem. Truck just would not start when hot sometimes. When it would start, the pressure was ok. Changed The pump 6 mos ago and haven't seen the problem since.
I thought it was the MAF to start with but I swapped one with another truck and the problem still showed up usually after a longer drive or towing.
That being said, as the previous posts said, would change the filter as a cheap maybe first and see if it shows up again.
If you have access to a lift, the pump isn't too bad to change in an hour or so. You can do it without pulling the tank, just tilt the tank forward to gain access to the pump.