Howdy, I'm new to this forum... although I'm not new to CTD. My '94 proved reliable and bullet-proof. I recently bought a new '05 2500 QuadCab 4x4, G56, 3. 73's... I've heard that deleting the Cat and muffler will either throw codes or 'de-fuel' the engine. Is there any truth to either of these rumors? Will deleting Cat and Muffler provide any mileage/performance enhancement as in the early 2nd Gen trucks? Also, was told that I needed a module with 'boost fooling' to delete Cat and muff? Any input would greatly be appreciated. 
