Magnaflow Muffler install / comparison

Installed a Magnflow muffler (pn 12588) today. The Magnaflow muffler is a straight through design and is slightly smaller than the factory muffler. Suprisingly the factory muffler also seems to be a straight through design. I'm going to cut it open to inspect before we recycle it.

The installation was fairly stright foward, but I did have bend / modify the factory hangers to make them fit. I kept the same hanger locations/number and welded everything. I don't want the exhaust to fall out.

Removing the cat back is easy. Drop the spare, jack up the rear for clearance, unbolt and remove. Careful not to damage the brake lines around the rear axle.

Some observations, the new muffler says it is 3" in and 2.5" out. These are inside measurements. The factory exhaust is 3" OD and 2.5" OD at the output. The existing exhaust pipes will slip inside the muffler pipes. The input fits perfect, but the output pipes need to be notched and pinched before welding because they do not fit tightly.

Also if you look at the factory muffler you'll notice the output pipes are offset and they are closer together than on the new muffler. Therefore they need to be spread apart to fit the new muffler. Also the new muffler does not install level side to side because the existing output pipes are not level. The tilt isn't too bad and shouldn't hurt anything.

The new muffler sounds almost exactly like the factory muffler. Maybe a little deeper tone at idle. It does not drone and sounds very good. Also it looks pretty good as you can see it through the wheel opening.

Is it worth it? For $115 and 6 hours, maybe, but if I'd spent the money for the entire cat back I'd be disapointed. I think this is a testament to how good the factory system is. The factory exhaust is a straight through design and does not pose much of a restriction at the 400hp mark.

I've attached before and after sound clips and pictures.









Videos
Before
DSCN2751 - YouTube
DSCN2754 - YouTube
After
DSCN2763 - YouTube
DSCN2764 - YouTube

Great job!! I love Magnaflow

Love mine as well. No drone, sounds nice idle throaty, but really growls when you let her eat. Looks great too...

Yesterday we took a little road trip so a few more observations. Initially I didn't think it was much louder than stock, but after driving it for a while it is quite a bit louder when accelerating, especially a slow acel between idle and 2500 rpm. It has a nice deep rumble, awsome. At highway speeds it is a lot louder right around 2000 rpm. Up to 73 mph it is fine, but anything more and the sound is a little loud. The wife made a comment about the truck sounding like the mustang, to which I just put my foot in it a little more It made nice background noise while listening to the race. Overall it sounds awesome and I don't think I'd want it any louder for eveyday driving.

so did you keep the resonator and every thing else is om? sounds good

What did you do to compensate for the shorter magnaflow muffler, just add an extension pipe?

My manga flow was a direct fit.

I don't have a resonator, at least I didn't see one. Yes I added a small extension to the 3" section to create slip fit between the muffler and exhaust pipe.

2010 has no resonator

it's a small muffler looking thing by the cat up front