I can understand the better breathing and free flow of the exhaust by losing the cat. Will the engine start throwng codes?? Will it increase the noise level??
Thats the thing with these trucks. Not all of them are the same. They each have their own personalities. Some will throw codes when you take off the cat. Some wont. Some will only when you tow anything. Some throw codes only when you stomp on the go pedal. Some throw codes when you drive by flower shops. Some dont throw any at all.
There's just no telling. None of my trucks ever threw any codes. Typically, the north east and California trucks have been the most sensitive when it comes to removing cats. However, I have a north east truck that I bought up in the communist state of New York and I never got a check engine light.
Most likely, you wont get any light at all. I never got one on any of my trucks for removing the cats. Either way, if you do, it wont effect driveability and your programmer can erase the code for you since they all have the ability to read and clear diagnostics.