I need a cat with 4" inlet and outlet. Does anyone have one for me or know where I should buy one?

 

Assume you know the cat that came on 12 valves was 3"x4".
You're talking big bucks for a 4"x4", would probably have to buy it brand new.

 

Yeah, but what about the cats on 2006 CTD's? Don't they come with 4" exhaust? So, they would have 4x4?

 

There are hundreds laying in a heap behind most muffler shops. They just sell them for scrap. Im sure you could make a deal on a used one-wont have many miles on them, and yes the 2006 is 4x4.

 

i had a 2004.5 cummins with the 600 in it.. so it had a 4 inch Cat on it.. i still have it.. just cut if off with a torch on each side.. not sure how clean the cuts were.. but its sittin in my garage.. new they are pricey.. but if you go outside a diesel performance shop and check their metal scrap bin.. i bet you find a few of them.. in a state w/o emissions testing ;x

 

I thought that thing was only a resonator, not actually a cat? My brothers has his removed on his 2000 CTD and it goes through emissions no problem and they do a visual check.

 

89-super early 94 = no cat
94-9812v = cat
98-early 04 = no cat (resonator)
04.5- present = cat

 

So that bullet deal under my 96 is a cat then huh? Learn something new everyday.

 

Magnaflow makes a h/p cat for diesels. I'd check it out!

Rick

 

Is this the thing right in-front of the muffler?
Because I couldnt find a cat anywhere on my truck...
where did they usually put them in 96?
close to the turbo or close to the muffler?

 

The cat is right infront of your muffler on a 96 , it is 3" in , and 4" directly into the muffler , no pipe inbetween.

 

thank you jkm