My f150 makes noise when I go up little hill or slowly hit the gas .Do you it is gas.Runs strong when you put your foot into it.Any answers would be great thanks Joe I hope you know what I mean it's like a rattling sound

 

What oil/filter are you using? could be the converters are rattling o the heat sheid an exhaust leak or you been using a fram filter and you been oil starving the valve train because of that..

 

Could be the timing chains to, mine does it from time to time. Didn't start till I switched to the all metal guides

 

Sure it is not pinging? Try some mid grade gas and see if it goes away. When looking up the number on my 98 4.6 computer for my 5 Star tune I discover my version of computer is notorious for pinging, strangely the 5.4 I swapped in doesn't ping at all.
Mike