Catyltic removal, Cat removal

[Bob4x4]

I loaned out mine for some testing,while it was out the only thing that changed was more noise and smell

 

[AH64ID]

I had removed mine about 4 months ago. I was getting about 19mpg proir to removing and now it is down to 15mpg. As far as performance it didn't help at all. I am going to put mine back on because the loss in MPG's isn't worth it. Just my 2 cents

I doubt that is your issue.

 

[BIGNASTY]

Put on a new exhaust on my 04. 5 and had a test pipe with header flanges so I could install or uninstall at will, when I lived in So Calif. I never noticed any MPG difference but did notice an exhaust note change with it in or out. I took it out when we moved to MT and have yet to reinstall, I have heard that they are big bucks so I will save mine for later.