Hey guys. I have a 98 5.4L, and I'm considering yanking the rear cats, but I have a few questions....

Is it illegal?
Will it cause my check engine light to stay on?
Will it cause the truck to run rich or lean?
I currently have no mufflers. Can I expect much difference in sound?
What other differences should I be aware of?

Thanks!

 

Yes it is illegal.

No your CEL wont come on.

Your truck will still run normal.

If you pull them off, i suggest putting some small mufflers on. Otherwise it will sound like complete s**t. Seriously.

 

x2 msall if you cut the rears with no mufflers it will sound horrible ive actually heard the exact set up your talkin about, 5.4 with ONLY pre cats
sounded horrible

throw some 10 series like mine

 

Dont do it if you have emissions, or a connection with a friend at your inspection station.