Thanks for the replies......can y'all give me the part number for the 24"

 

Had to go check the warranty card to make sure. It is a 12286.

Yesterday we drove up to Oklahoma City and back (260 mi. round trip). Like I said before the 24" was installed on March 31. Wife ran the satellite radio all the way up to OKC and back. No problems hearing the radio at all. With the radio off I could hardly hear the 24" while cruising I-35 at 70 mph. Could definitely hear it on the on ramps, from the stop signs in town, and moving around town in the 25 mph speed zones. I guess if you like a lot of noise then the 24" is not the way to go. I don't care to hear a loud exhaust while crusing down the roads, so the 24" is perfect for me. Wife and two sons didn't complain so it has worked out OK. I am still wondering how an 18" would sound, but have no desire to change what I have now. I guess the loudest I had would be the 71 Mach 1 (351C) 4-barrell with duals that I purchased new a month after a 4-year hitch in the Navy. I replaced the two stock mufflers with glasspacks. I was 22 years old back then and that was quite a few years ago. I am totally comfortable with the 24". The S&B CAI from Troyer should be here Tuesday. Will be pulling the 5K lb RV to Mississippi in 10 days. Wondering how the Magnaflow and the S&B will work out.

2007 Silver Screw FX4 3.73 LS 5.4 w/24" 12286 Magnaflow

 

PLEASE post back after the trip with the RV. I would love to hear your opinion about it while towing. I want to do exhaust but I don't want to regret it when I'm towing the TT.

 

I'll do that, no problem.

Noticed that you are running an 03 about like what I had before. Mine was a 03 FX4 Scab 5.4 3.55. I pulled our heavier TT with it several times. Wet the TT weighed about 6K. The 03 pulled fine on level roads and the low end torque got it up to cruising speed (60 mph w/TT behind) with no problems. The 260 HP 5.4 with 3.55 was a little weak going over the mountains in New Mexico on 1-40 and in eastern Tennessee. Hardly ever pulled the TT in the mountains anyway so it really wasn't that big of a deal. The 03 was completely stock, no mods at all.

With the new 07 I've got 40 more HP and the 3.73. Our new TT is about a 1K lighter than the old one. Pulling 5K with the 3.73, magnaflow 24" and the S&B there shouldn't be any problems at all.

I'll update you on the pulling experience after the trip to MS.

2007 Silver Screw FX4 3.73 LS 5.4 24" Magnaflow and the new S&B CAI (should have it installed in a few days)

 

Going in to shop today to have the 18 replaced with a 24. The drone at 75 is to much and with a 2.5 ton truck performance is a pipe dream.

 

The longer trips that we take usually take us down through the Smokey's and it does OK. I'll never set any speed records, but it handles it very well. My TT tips the scale at just under 7000 pounds.

 

Trooper180 - - - Thanks for the input. I have a question for you. Magnaflow makes a 22" (5x11) muffler that is a little quieter than the 24"(5x8). Do you think it would be too quiet compared to your 24" since you have had a chance to expierience the 24.

I know there are some people here that have had the 22 and/or 24. Anyone that has compared or used the 22" or 24" Maggie....please advise.

 

I too eagerly await the good/bad news on these mufflers. I'm supercharging my 4.6L, and enjoy hearing it, but hate the endless roar/drone when towing the travel trailer.

 

The 24" is pretty quiet cruising down the highway at 70. Today we made a quick trip to Dallas and back. I was pretty sleepy so I stretched out across the back seat. With the radio off I could barely hear the 24" maggie.

If the 22 is quieter than the 24 then I don't think you would be happy.

For my kind of driving the 24" is just right. Pretty quiet at cruise speed and noisy enough while accellerating.

More on this after the 5000 lb RV pull to Mississippi and back.

 

Hey Westtex, I have a Magnaflow 12286 sitting in my storage that I used for a few months if you're interested.

 

18" all the way.

 

I am going to be replaceing my stock muffler soon with a Magnaflow 18". What offset do I need?

 

Pretty sure the 05 would be the same as my 07. I had the stock muffler replaced with the 12286, which is Offset/Center. One inlet is centered and the other is offset. The link below is for Magnaflow's Website and has photos of each muffler they sell.

http://www.magnaflow.com/02product/s...ne=main&id=301

 

It probably doesn't matter.

The OEM muffler is welded on the outlet side and is so enormous that they will have to cut the pipe and add an extension to reconnect anyway.

 

What would you take for it?