I currently only have front cats on my truck and need some new ones. I want a high flow and was wondering if magnaflow has a direct replacement for the front cats? If there is a part # that would be sweet

 

Just wondering which cat more represents my stock front two cats, the 94306 or the 94106 as for sound since that's what I have currently?

 

#94106 are 9" like the pre-cats, but the pre-cat replacement part # is 99176HM.

 

im looking to do the same thing i took my back two out and i want to put high flows i was wondering if would make it louder and perform better (mainly not effecting mpg) and not mess up my custom tune?

 

Leave your front 2004 cats alone, replacing with hi-flows will not make it louder. They are already short body hi-flow cats, and best of all, the O2 sensors aren't messed with. Only reason to change them out aside of a clogged cat would be LTs.

 

Ok sounds good thank you for the info they arent clogged yet so ill just keep them stock then