I am wanting to put high flow cats on my truck and take out the 4 stock ones. Was told today by the local shop that I had to have specific ones that they were not uiversal. Is this true? All yall that have high flow cats what are you running? My truck is a 2004 with 5.4 thanks

 

They're just trying to scam some extra cash out of you, 2.5 in and out will work

 

And find another muffler shop...

 

ok thats what i figured, thank yall.

 

Just be sure to get the correct ones that can handle the heat that a larger engine. Not all universal cats are really universal. Magnaflow 94106 are the cats most who go after market are running.