alright well my truck is getting such shitty gas milage n im trying to figure out what is causing it. my truck now has no muffler and i was wondering if not having a muffler n haveing no back pressure might be cuaseing it. ALSO i do not have that vapor box or what ever that box thing is that is linked to our gas tanks on what does that do what that be a reason why im not getting good gas milage? lemme know SOON!!!!!