If it's not low on oil when this happens, then it's very possible the pump is weak.
You should verify the pressure reading using a manual gauge before condemning the pump.
That is the purpose of checking the pressure manually. If the pressure gets too low at idle when the engine gets hot, then you likely need a new pump.
It's not an extremely bad job but it's no piece of cake either.
The engine doesn't have to come out but the oil pan has to be removed in the truck.This usually means unbolting and jacking the engine on most vehicles.
To be any more specific, I would need the engine size and 2WD or 4WD.
OK, I'm going to need the 8th digit of the VIN#
There are 2 different 4.6 engines and there is a BBIIIIIIIIIIIIIIIGGG difference in the labor time to change the pump
If the 8th digit is a "W" here's the part price and labor time.
PartOEM PartPriceOil Pan 33 - Oil Pan XL1Z6675CA $91.33
LevelMfg.WarrantyStandardOil Pan Replace 1.4 hours
Now it the 8th digit is a "6", then the pump is in the front of the motor and not in the pan and the labor is quite different.
PartOEM PartPriceOil Pump 35 - Oil Pump 5L3Z6600AA $62.76
LevelMfg. WarrantyStandardOil Pump Replace 11.6 hours