Headers question- if I’m looking at my truck from the drivers side, or passengers side, there’s something disconnected. There’s a hole about 3 inches in diameter...behind my front tire. But kind of inside where the engine is? I saw it when my truck was jacked up the other day but I can’t find it again so idk what side it’s on... about the same size hole as what I’ve seen headers connect

 

Sounds like somebody stole your catalytic converters. Take it to a muffler shop. Don't drive it too far like that it's bad for the exhaust valves. They can warp.

 

Must be referring to exhaust manifold. If not what type of headers ? Exhaust Y-pipe is 2.5", looks larger because it's flanged at the ball connection . I bet the Y-pipe flange bolts rusted away and the pipe separated from the manifold ball flange. Because they do that with these trucks, specially in the rust belt. The two bolts rust until they're no thicker than a pencil lead before they snap.