anyone know what the factory tubing sizes are for exhaust on a 2004 ram hemi? and i noticed i have 2 mufflers and a catty on mine from the factory.

 

the piping sizes? Should be 3".

 

On an 04 you have it slightly backwards but are on the right track. You have two cats right behind the exh manifolds. Then a resonator and a muffler at the end.

I think it is actually 2.75" but the 3" flowtech pipe from DMH will work obviously.

 

Piping is 2.5 from the cats to the Y then 3" the rest of the way back.