ford f150 runs great till it warms up then it starts to knock has low miles on it 50;000

idle as you stop

change grade i think its 0/30 or jus 30,i had a company truck do the same thing,when the changed grade of oil the sound went away!!!

Is the noise upper or lower

I have the same issue but its only when truck is in drive or reverse but not when its in park and idling. Ive been told its possibly just the exhaust pipe is loose and is rattling. Is this true? Or possible?

low oil pressure is likely the problem, what year is the truck?, late 80's up to mid 90's 302's (5.0 litre.s) were known to have oil pumps that wear out overtime.

It could be many different problems. If its upper noise it could even be injectors. Nothing to do with oil, or it could be lifters or valve noise. If its lower end noise it could be that you have a rod knock or even a spun bearing. Does your truck have an oil pressure guage? Check it to make sure that you have at least 40psi. Beter if between 40 & 60.