4.0 muffler removal

[RoBB_D83]

I recently removed the muffler right at the flange behind the cat just because i wanted it to be loud. My question is will it improve or hurt my fuel mileage?

 

[Jay FX4]

Did you just remove the muffler and everything after that, or everything after the cat?
Either way, I would imagine that would hurt fuel economy. You need some back pressure. And if the exhaust is exiting right under the cab, that's not good because of the fumes.

 

[Fx4wannabe01]

it will hurt performance immensely

it will hurt mileage significantly

it will hurt your ears at anything above idle and under load

it will smell oh so sweet



You want louder, how about doing it the right way? Get a new exhaust.

 

[DSFD505]

I had to run my old ranger this way when my flowmaster rotted off and let me tell you, never again. Yes it was loud and could hear me coming miles away. The sound was just as nasty as those fart can mufflers on the ricers.