Hey everyone,

You might have followed along with my recent Lean Code issues. For the most part, I seem to have solved those after fixing numerous vacuum leaks and installing new injectors (after one of the refurb ones failed and almost killed the motor!). My SES has stayed off for several hundred miles.

• I'm still getting poor fuel mileage. I have another ECU to swap in and see if that helps, but I also know the Cats are on their way out.
• After running the truck rich for a few thousand miles I'm confident that cats are in worse shape.
• They tick occasionally and also smell like sulfur occasionally. Also my mechanic has mentioned that the rear O2's cycle too much indicating failing cats. I have noticed the same thing.

All of this to say, I am going to replace the Cats and wanted to prod into the infinite wisdom of the forum!

I have ready good things about the Walker Cats. They are about $100 a piece. Similar price to the Magnaflow units. Any real world experience with the Walker or Magnaflow High Flow Cats that can be shared? I have a good local fab shop who does good work at a solid price that will do the install.

I'd prefer the truck to stay fairly quiet, but I already have a small center muffler since mine was falling a part when I bought the truck. Can anyone share experience on the noise levels of the Walker or Magnaflow cats with an aftermarket center muffler?

Lastly, while they are in their cutting away the cats I would like to replace my rear muffler section since it's a little rusty and I don't like the Aesthetic of the rusty tailpipe coming out the rear of an otherwise very clean truck. If I do that, I can go with the Lucky8 rear section, or the Lucky8 Cat back setup which includes a stock sized center muffler.

Does anyone run the Lucky8 factory replacement exhaust? Does anyone know who's parts they are, or do they build these in house?

Link to Lucky8 Cat Back system

All of this has been discussed a bunch, but of course, like everyone, I had to ask for myself...

My goal is to have a "not much louder than stock" sound, while hopefully helping the motor run a little better with new Cats. Of the truck was a manual a little more noise would be nice, but Autos just don't have an appealing sound when they're loud to me. Too sloppy. I'd rather cruise in quiet comfort.

As always, thank you for you input. Opinions of all sorts are welcome!

 

i run the Walker Cat Back on my '04 and while it is a little louder than stock, it's not much different.

 

Same here, not much louder than stock with Magnaflow Stainless Y pipe and cats, stock cat back.

 

I run the Magnaflow muffler and deleted the resonator behind the muffler. It sounds like a nice roar, but not too loud. You would not turn your head and think that guy is an *** if I drove through your neighbor hood.


This was filmed right next to the Rover by my dad.

 

Thanks, great info.

Good to know on the Walker cat back system. I assumed the walker and magnaflow cats would make more noise than stock but it doesn’t sound like that is the case.

 

I have Magnaflow 94105 cats and a Magnaflow 12586 muffler. Cats are really good because they slipped right over the existing pipes so a monkey can make a solid weld. Cut the old ones off, slip the new ones on and weld them up. The Magnaflow 12586 muffler might be exactly what you are looking for. It’s only 2” shorter than stock and exhaust is just a little deeper, no drone. If you put your foot in it you can create a rumble but it’s not going to get much if any attention in traffic. As for the rear section of my exhaust I deleted the rear resonator and I would recommend doing that. For no other reason than making the exhaust tone deeper. You mentioned your rear section was rusted, I would have my muffler guy just weld up a new section. Probably way cheaper than buying and shipping a prefab unit.

 

I’m having issues with my cats, someone fitted mini cats but still get the amber engine light up,
it’s had several trips to the sparky for bank 2 issues, will these cats take the sensors as well ?
and hopefully fix the issue

 

I honestly don’t know if they will fix your specific problem. I do know that if you need cats that these are moderately price, fit well and didn’t throw any codes on my truck.

 

Thanks @Frank4. Exactly the input I was looking for!

I will probably go with the Magnaflow Cats. I have a smaller stainless muffler at the moment that looks similar to the MF one you posted. My truck is still pretty quiet but has a nice rumble, so I'll probably leave it as is for now.

What sort of sound difference does deleting the resonator make?

 

Another question on the topic - How poor was your fuel mileage with old worn out Cats?

I am currently getting 11 mpg's with mostly city driving. I drive like a grandpa, maybe 5 over the speed limit max with very minimal hard acceleration. My D1 would usually get 14mpgs+ around town, so I know there's more MPG's in it.

I know my Cats are pretty clogged based on O2 readings, ticking noises, and they smell bad sometimes. Also I've had lean codes, and a failed fuel injector so the truck has been running super rich. Pretty sure they're toast.

All of that to say, how bad does MPG get with worn out Cats? Do you think that's likely my issue or should I be looking somewhere else? No check engine light or misfire, decent/normal power, truck runs good.