Well I installed my new Magnaflow cat back, 15000 SI/SO on my 11 5.0. It sounds nice when you get on it, but has no tone when idling. I'm thinking that I will need to replace the front pipe which has the resonator on it. Anyone know of a source for this pipe? I will likely visit a local exhaust shop and see what they can make up for me.

Anyone looking to do exhaust on these trucks should look at replacing the resonator too.

 

So, the cat back does not replace the resonator? Is there any perceiveable drone when cruising on the highway at 65 or 70 mph? How many miles/days since the install? A custom exhaust shop can cut out the Resonator and install straight pipe.

Thanks, James

 

I have true dual 2.5 inch pipe into magnaflow dido 18 inch now
I had glasspacks on for 60 miles and it was louder than my mustang that has no cats and no mufflers right now. This thing will be loud if you want it. Anyways now with the magnaflow there was a little drone at 70 but I had my stock exhaust and put the little vibration canceler thing (whatever its called) on and got one from another truck and put it on the other pipe and now no drone.

 

That's actually how I like it... quiet and not noticed until it's time to be nocited

 

Nope, the resonator remains. I've only had it on one full day or about 30 miles. I'm not sure what I will end up doing, but I was sort of surprised by the overall quiet nature of this cat back especially when I figured it would sound very similar to the SI/SO Magnaflow that I had on my 07 5.4.

There is no drone or any unwanted noise that I've noticed so far.

 

I would give it a few thousand miles. It will break in slowly. I had a 22" Maggie on my '07.5 (248 hp) STX with the 2 cat 4.6 - 2V engine. I initially had a 3" SI/SO 50 Series FM on a 3" catback. I installed the Maggie two years later. It was quiet for the first few weeks. It eventually started to drone at 70 mph and it could be felt vibrating through the driver's side floor pan. It would also give me a headache after a 10 hour trip.

I would like to install a a SI/SO muffler on my '11 STX SCab but do not want the undesired drone. I can handle the dual 14" Maggies on my Gen. 1 L. But, I am not looking for any highway drone. I do like the 5.0 exhaust note at part and WOT. I would like to hear a slight exhaust note in daily driving, a decent growl when on the pedal and stock at 70 mph. I have read a few reviews on the Aero Exhaust Stealth 217 muffler which is similar to a 24" Maggie. Their Stealth series muffler is supposedly the quietest performance muffler on the market and even quieter than a Magnaflow.

Keep us informed on you exhaust and if you decide to remove the resonator. How much of your driving is done on the highway?

Thanks, James

 

I put a SI/SO catback on my 2010 w/ 5.4 V-8 (Magnaflow 16518) I have been getting some unwanted cab drone so i called Magnaflow and asked them what I could do to get rid of the drone.The tech said to install a resonator muffler before the catback muffler. He suggested going with this Maganflow part #14419. Its a 3" in/out, 4" overall round muffler.

 

I ended up trading my '07 STX for an '11 STX. I received a reply from an Aero Exhaust retailer this morning. Aero Exhaust no longer manufacture's the Stealth Muffler. I guess this is the reason I found it at a 43% savings. I'll pass... I guess I'll stick with the factory muffler and call it a day unless I hear someones 5.0L in person. I can no longer deal with the drone and vibration that comes with it.

I tried the resonator in front trick on my '05 Crew Cab Titan with a 22" Maggie and it reduced the amount of in cab drone to almost tolerable levels. I guess being around Turbo Prop and Jet aircraft for 21 years has left me a lot less tolerable to high frequency drone than I used to be.

 

You might try taking your resonator off. It might pick up a little sound.

 

It has crossed my mind a time or two. I might stop by the exhaust shop and see how much they will charge to remove the resonator and use butt clamps with a piece of stainless pipe. It would be easily reversed if I don't care for the exhaust note. I believe the resonator pipe is 2.5".

 

I will keep you all posted. I live in the country and run about 60 or so on most of our country roads. I've not yet heard any sort of drone. I never did with my 07 5.4 either, with the same Magnaflow SI/SO.

I will be trying a pipe without the resonator just for the heck of it. I just have to find someone with a pipe or have someone make one up for me.

Even tho it's mighty quiet, it sounds much better then stock.

 

Act what's your part number I'm trying to piece together a sys right now and am think 22" si/so 3" muffler w/res wood do

 

I listed P/N 15000, when I first posted this. Never did anything about the resonator.

I remember reading here or one of the other F150/Ford Truck boards that someone listed P/Ns for a variety of pipes with and without resonators. But I don't remember where I saw that.

Sorry I can't offer anything more. Good luck!!!

 

Myself as well-part of the reason that I love the new 5.0 so much. Quiet most of the time, but awesome sound(even stock) when you get on it.....