I want to replace my stock pipe with a 5" aftermarket exhaust that improves HP and sounds nice without being too loud. I would like to get rid of the catalyst but I am worried the O2 sensor will screw up the computer.

any recommendations?

thnx

 

You need to educate yourself on diesel basics, and specifics of the 7.3L, before you go modifying things you clearly don't understand.

Diesels do not have oxygen sensors ( Well, some very new ones might, as part of the emissions controls; but certainly not a 7.3)

Most 7.3L's never had "catalysts". IF yours does, you can remove it with no negative side effects.

While some will disagree, most agree that 4" is the biggest exhaust that most 7.3L's need. ( except for very high power custom builds) All a 5" exhaust will get you is more noise, and more aggravation trying to make it fit in places where a smaller pipe was meant to go.

 

My 2002 7.3L Diesel Excursion does not have a catalyst and still qualifies as LEV (Low Emissions Vehicle)

I have 4" MBRP Cat-back (including 4" downpipe) and it sounds throaty, but not loud.

 

God only knows what's on that truck down in Peru. Wasn't there an assembly plant in Brazil or something? But either way a 5" exhaust is overkill. 4" may help a little but if the truck is stock otherwise it won't make much of a difference, if any.

 

I went with the 5 inch over the 4 purely for the difference in sound. It was a bear to make fit right and is very tight. It will also require some finesse if you have a gooseneck hitch. Mine was rubbing on the hitch and it took some creativity to make fit. If you want more flow but not as much sound, stick with the 4 in. The 5 inch is loud

 

I bought a 4 inch and it was not worth the money spent. Not a total waste but not needed in my opinion. I kinda wish I would have just left the stock on. Live and learn.

 

"Most 7.3L's never had "catalysts"."
__________________________________________________ ______________________
The only 7.3's that were "catless" were the '99.5 through the end run of 7.3's with an auto trans. Earlier than that and all manual transmission trucks came with a CAT. From the factory at least.

 

No, they didn't.
1.) My '00 is a manual trans, and it did not come with a cat from the factory. The passenger valve cover list, near the bottom, all the emissions "systems", the vehicle had from the factory. IF it had a cat, it would be listed on the sticker. Mine doesn't.

2.) Also, no OBS 7.3L had a "catalyst". They MAY have had a particulate filter/trap. BUT, they are inert. As they have ZERO PGM content ( platinum group metals), they are NOT, by definition "catalysts", as they have no means of initiating a catalytic chemical reaction.

Even the '99 up, and including 6.0L's, barely qualify as "catalysts" as most have only trace amounts of PGM. It was only in 2008 (6.4L), when the emissions laws changed for light duty diesels, that diesel "cats" and DPF's start to have actual PGM content and catalytic functionality. Same for GM and Dodge. In the scrap world, pre-2008 diesel "cats" are called "junk diesels", and are worth $0-$10 Dodge Cummins are a slight exception, as they introduced their '08+ DPF/CAT system in mid 2007, so 2007.5+ are good for Dodge.

 

 

I put a prebent five inch exhaust kit on my '99 F350 Auto crew cab 4x4 with DRW, around 7-8 years ago. It's loud, but I'm half deaf anyways...my wife tells me


I had no issues with clearances.

 

I spent $86.87 on a muffler delete pipe on a stock exhaust thinking it would reduce EBP and show some noticeable difference in turbo performance.
Nothing like throwing $ down the exhaust pipe!
All I got was a louder truck and an excuse for any cop that wants to be an @#$%^&* to pull me over. Not sure how or if they will write a ticket though since I am usually out of state and the home state/county has no inspection requirement.
Plus it's only objectionably loud if you are really getting on it.
Lesson learned about mufflers and power gains. DDT