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MagnaFlow Performance Exhaust Muffler 12578: 3'/3' Inlet/Outlet, 5x11x22' Oval, Stainless Steel, Satin Finish

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$167.00

$ 82 .99 $82.99

In Stock

1.Size:2.5 In. Inlet/outlet


About this item

  • SIGNATURE MAGNAFLOW SOUND - The 5" x 11" Oval body of muffler 12578 is engineered to deliver the deep, resonating sound that MagnaFlow mufflers are famous for.
  • DYNO-PROVEN PERFORMANCE - Extensive dyno testing is used to ensure that this 5" x 11" Oval muffler increases engine power and performance by improving the flow dynamics and evacuation of exhaust gases.
  • OPTIMAL ARCHITECTURE & CONSTRUCTION - The internal architecture of this muffler features a straight-through perforated core with two-stage acoustic packing which maintains the velocity of exhaust flow while generating a smooth, deep exhaust tone.
  • UNIVERSAL FITMENT - 12578’s universal design enables custom muffler placement and orientation to meet the particular spacing and mechanical requirements of your vehicle. Professional installation is highly recommended.
  • LIMITED LIFETIME CONSTRUCTION WARRANTY - Performance that lasts. Enjoy worry-free ownership knowing that you're backed by MagnaFlow’s limited lifetime construction warranty.


Fully reversible and featuring a free-flowing, straight-through perforated stainless steel core, stainless mesh wraps our acoustic fiber fill to deliver a smooth, deep tone for your custom exhaust project.


Customer
Reviewed in the United States on February 17, 2025
Was not not welded on the one side of the muffler had to pay some one to do it when it should of been done from factory
Sean Andres
Reviewed in the United States on May 18, 2022
perfect balance of nice sound but no drone on hwy tripswish I'd bought from amazon but paid extra at local muffler shoppro tip buy on amazon and then just have installed! Save $50!
Robert
Reviewed in the United States on August 31, 2021
Solid muffler at a reasonable price! Installed on my 2007 F2650 Super Duty. Muffler inlet and outlets are slightly oversized to accept the 3" stock exhaust pipe - Slipped right in! I just had to cut the old muffler off and weld the new one on. Sound is slightly louder then stock.
Customer
Reviewed in Canada on March 1, 2019
Muffler fits over 3 inch pipe and has a nice sound .
EL
Reviewed in the United States on September 25, 2015
I was looking to replace my factory muffler on my 08 Dodge Ram 1500 Hemi and this was the perfect choice for my needs. It's slightly louder than the factory but not by much, I didn't want to be "that guy" that wakes everybody up at 5am when I start my truck. It also has a little bit of a deeper tone too but sounds great! Be carful when selecting a Magnaflow because they don't do the best job advertising if the model you selected has sound deadening material inside. You gotta check the part number against their website to be sure.Mine does and that's how I wanted it but almost got the wrong one that only has baffles and that would of been really loud!
buildit
Reviewed in the United States on August 28, 2014
Very nice muffler. It's huge and VERY quiet. I used it on a 5.3l v8 with a 2.5" Y pipe going into a 3" rear section with this muffler. I have used about 25 of their other sizes and they always work well.
John Fugate
Reviewed in the United States on June 29, 2013
I pick this muffler because it looked like t he closest fit to the original. I was surprised how well it fit into my 2000 F250 super duty truck. Sure it is not a direct fit, but all i had to do is modify the rear hanger by hamering out the band to match the shape of the new muffler and cut the front hanger loose and weld it to the new one. It fit better than i expected. It was also quieter than I expected. that was a nice surprise as i use the truck to haul long distances some times.Very pleased.
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