I had a situation like this and the strainer on the end of the pick-up tube on the sending unit in the tank was clogging from the sediment in the tank. When the sediment was agitated and the pump was pulling, it would starve the line of fuel, causing the truck to die. We removed the sock from the end of the sender pick-up tube and installed a good filter in the line between the pump & carb and never had the problem again. After running a few tanks of fuel through it and changing the filter a few times, the sediment was no longer floating around in the tank and the problem went away.
The fuel pump test mentioned above will isolate the problem to the fuel pump, if that is the issue. Good luck.
