I have a 05 f150 fx4, i have 305/35r24 tires on right now and gonna be getting new ones here in a bit because these tires look to small for the truck, i have been looking at the pirelli scorpion atr which is 325/45r24, ok my question is would that tire fit? and if not what suspension upgrade would i need?

 

I'd suggest keeping what you have and lowering the truck. I think a set of lowering shackles out back (to level the truck) would make a huge difference. Also, I'd be afraid of any of the Scorpion ATR tires after all of the problems with the OEM Ford tires.