Will Catalytic Converter Get Rid of Drone?

[AH64ID]

The cat should be first for the heat, then the muffler. I really doubt you will need a resonator at all, the cat on these trucks does a great job killing the drone. I ran cat only for a while and had no drone at all, even when towing.

[Wild and Free]

The Cats are short enough that you could piggy back the resonator directly behind the Cat if you wanted and probably have the same result.

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The cat should be first for the heat, then the muffler.

I really doubt you will need a resonator at all, the cat on these trucks does a great job killing the drone. I ran cat only for a while and had no drone at all, even when towing.

I still have the factory exhaust with nothing but the Cat left and the drone is killer while towing, just normal DDing is tolerable but once there is a load on its horrible.

[StewB]

I've decided since I already have the cat and the resonator coming I will go ahead and install both. I would like to do the cat first and see what happens but time is running short before I move and I need to just get it done so I can work on other things. I see no compelling reason not to put the cat first so I am going with that. If it doesn't work properly there's no point in putting it in at all. I'll place the resonator directly behind it where it will still be under the back seat. Though the resonator might not be at peak efficiency, I think it will be more than adequate when paired with the cat. I'll report the results when i have something meaningful. Once again, thanks for helping me think through this. StewSent from my iPhone using Tapatalk

[AH64ID]

I still have the factory exhaust with nothing but the Cat left and the drone is killer while towing, just normal DDing is tolerable but once there is a load on its horrible.

Interesting, I didn't have that problem. I didn't like the sound and the soot from the SJR going into the cat so it's taking a nap in the attic, but I drone wasn't a real issue. Are you short any exhaust hangers? I know a few years ago when muffler only deletes were popular a lot of drone was caused by lack of exhaust hangers.

[Wild and Free]

Interesting, I didn't have that problem. I didn't like the sound and the soot from the SJR going into the cat so it's taking a nap in the attic, but I drone wasn't a real issue. Are you short any exhaust hangers? I know a few years ago when muffler only deletes were popular a lot of drone was caused by lack of exhaust hangers.

Been so many years ago since I did the muff delete pipe I can't remember if it is not utilizing a hanger or not.

[dripley]

I am going out on a limb here and say a piece of unistrut could possibly be involved. :think:Rednekkedy.

[diesel4life]

We have a winner! :

[StewB]

Well, to answer my original question, adding the Magnaflow cat in the stock position with an existing Banks Monster muffler doesn't kill drone completely. It somewhat deadens the overall loudness under heavy throttle with a 13500 pound load, and it makes the drone more tolerable. At idle it sounds pretty much the same outside but much quieter inside. Tomorrow I am going to add the smaller FTE resonator about 6" behind the cat, which will put it directly under the right rear floor board. Will report soon with more info. StewSent from my iPhone using Tapatalk

[cajflynn]

The resonator needs to be as far forward as possible to work properly.

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The resonator needs to be as far forward as possible to work properly.

[AH64ID]

Interesting. The OEM resonator from the megacab is the last thing in line, and is on the axle up pipe. It works great in that position on my truck.

[StewB]

The resonator needs to be as far forward as possible to work properly.

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The resonator needs to be as far forward as possible to work properly.

Several have said this and I would agree except that I was also putting in a cat. I had to make a decision whether to maximize the effectiveness of the cat or the resonator. I chose the cat because it takes heat for it to be effective and I felt putting the resonator ahead of it would dissipate too much heat. I probably wasn't clear about it, but my first priority is to pass a smog test even if it means the resonator performance is slightly diminished. Additionally, because of what AH64ID said, I don't think the resonator's performance will be affected much.

Stew

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[StewB]

For the record, the cat alone with my Banks monster muffler didn't get rid of the drone. When I added the smaller FTE resonator between the cat and muffler about 8" behind the cat, no more drone...period. The test--hauling 22,000 pounds up hundreds of 6 to 10% grades along the Rockies in Alaska and British Columbia.