mideerslayer

After looking further into my truck its leaking at the driver side frt cat, and the passenger side frt cat is making a rattling noise inside

So Since I'm super cheap but want to to everything right, what is the best but cheapest way to replace the exhaust from the manifolds back?

Can I use just one universal cat on each side and have a o2 sensor in frt and behind the cat So a total of 2 universal cats and 4 o2 sensors, and then one muffler?

Or should I do as above but go with dual exhaust and have 2 mufflers?

The truck runs great, looks good just has 207,000 miles and rust on the bed. Purrs like a kitten and I dont want to go buy something else and then have to worry about the what ifs, I already know this truck

My wife is about to make me sleep in the garage as I am driving her crazy about this LOL

Jbrew

You already have a exhaust thread going, -

https://www.f150forum.com/f6/exhaust-question-440082/

Having two threads same topic isn't cool.

mideerslayer

Sorry, it is a different question all together, so I figured I would start a new topic? Not like there is so much traffic on here that its clogging up the site?

Jbrew

Really lol. Yea, I disagree.... all together. Very inconsiderate.

mideerslayer

Can I remove the other post? As this is the one I would like to have answered? I haven't been around forums a lot since facebook took off lol but I think there much better to get real answers

Jbrew

You got that right lol.

So your manifolds are fine, no leaks ? Pay special attention to the passenger side manifold in the back, they like to leak there. Best way to handle the up stream cats is to replace them with direct fit. Just the cats themselves as that IS the cheapest way. Just make sure the manifolds are good, specially the passenger side because that's a much larger fix which involves the transmission mount and exhaust damper (hanger bushing problem)....they both wear out and stress the manifolds at the rear. That's what snaps the bolts, creating leaks.

Yea, they sell upstream cats for your specific application fairly cheap..just the cats. Third party makes no difference here.

mideerslayer

If I just cut out the frt cats and put pipe in is place and run just the rear cats will that be ok for the truck?

The rear cats are fine its the 2 frt ones that are the issue

I am just looking for multiple options. I keep getting told to just cut all of them out and run a straight pip on both sides and a muffler but I want to get use out of this truck and and not screw it up

Jbrew

I can't believe anyone would tell you that. You can have that done if you like, but you can't do that. Your going to need some custom exhaust work...nobody does that with the up-steams unless they are running a long tube header set up.

I would most definitely those folks to buzz off, delete them if possible.

Upstream cats need to be replaced, it's the easy and cheap. The smaller up-stream cats are more restrictive than the rear (downstream) but needed with the factory tune AF settings. The rear cats can be deleted and straight piped, not the upstream, not easily anyway...that would cost yuh.

I already posted the easiest and best solution a few days back, why do you keep avoiding/fighting it ?

mideerslayer

Sorry if you think Im fighting or avoiding your answer, I'm still learning the ins and outs of this truck so I am just asking the same question different ways, its a learning curve.

Let me ask you this, I found the smaller direct replacement frt cats online, if I was to cut out the old ones, would the new ones slip in place of do i need a special tool to flair out the pipe to allow it to slip on to the old section?

Trying to do this myself if I can but limited tools and space

If Not I can take it in but Im sure they will charge me dearly if I bring my own parts in

Again thank you for your help

Jbrew

Working on exhaust is never fun or easy. That's because the components rust and fuse in place and have to cut out. I've replaced the the up-streams myself once on these models. My first and last time about 11 years ago. The up stream cats connect to the manifold ball, you won't have to cut it there, HOWEVER, you' ll have to remove the manifold exhaust flange bolts (2 bolts bolts per manifold). Your chances of success are pretty good, I removed 3 of the 4 successfully then broke one. If that happens your going need a few good drill bits, the bits MUST be Cobalt M42 series (must be M42 HSS solid cobalt bits, NOT M32 coated, like say DeWalt bits) or you won't have much success drilling that out with the manifold in place. If you don't have a jobber set in your arsenal yet, this is what you want for automotive -



So that's ^^^ the only problem you MIGHT have at the manifold ball connection. Pre-treating the bolts with a good penetrate such as Kroil or PB Blaster would help..Kroil is better is you can take the smell lol.
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The connection to the exhaust side will have to be cut. If it were me, this is were I would eliminate the rear cat completely and piece in a metal pipe section. You don't require the rear cat on this vehicle, exhaust shops won't use a dual cat set-up on these trucks anymore..obsolete. They use one compliant cat vs two now a days. In this case (your case) , the upstream by itself is plenty. Your AF's are well within parameter margins of the factory software (tune). What this means, No CEL, -the vehicle will perform fine, perhaps a little better if anything and you'll will pass MOST emissions testings. So offing the rears at this time would make things much easier and in most cases (states), legal to run. In other words, you don't have to sweat removing the rears. I included this info in my reply because your not going to have much choice once you get into replacing the upstreams. The rear cats are too close to the upstreams to fudge a solid connection to without the correct tools for that job. You make that decision when you come to it, you'll see exactly what I mean once you get into it.