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Flowmaster American Thunder Axle-Back Exhaust (05-09 V6)

Item 18404
Call a Mustang Enthusiast at 1-877-887-1105
M-F 8:30A-11P, Sat-Sun 8:30A-9P
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Market Price $301.99 You Save 12% ($36.04)
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$265.95

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    Features, Video & Details

    • Aggressive Flowmaster 60-Series Delta Flow Sound
    • Polished Stainless Steel 3.5" Tip.
    • Durable Aluminized Steel Construction.
    • Includes One Flowmaster Muffler
    • Fits 2005-2009 V6 Mustangs.

    Review & Installation Video

    Review & Install Video

    Flowmaster Sound . The Flowmaster American Thunder Axle-Back exhaust system will improve your 2005-2009 V6 Mustangs exhaust flow for an increase in power and a throatier muscular exhaust note with their patented chambered designed muffler.

    Quality Construction. Constructed from durable 2.5" 16 gauge aluminized steel tubing for it's corrosion resistant properties the Flowmaster axle back features a specialty 5" X 10" chambered 60 Series Delta Flow American Thunder muffler with a 3.5" diameter polished stainless steel tip for muscle car looks and sound. As an added bonus the tip is embossed with the "Flowmaster" logo for true custom styling.

    Fitment. This Flowmaster American Thunder Axle-Back exhaust system is designed to fit the 2005-2009 4.0L V6 Mustangs for both great looks and great sound.

    Technical Note: Americanmuscle recommends adding the 2005+ Mustang 304 Stainless Steel Exhaust Hanger Kit from the drop down option above, to provide more strength, stability and a cleaner installed appearance. If you have a 2007 Mustang you may need the kit for correct installation.

    Fitment: 2005 2006 2007 2008 2009 Details

    MPN# 17421

    CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

    What's in the Box
    • (1) Muffler assembly
    • (1) Exhaust Hanger
    Installation Info
    Tech Specs
    Axle-Back Exhaust Specifications
    Piping Material: Aluminized Steel Tip Material : Polished Stainless Steel
    Piping Size: 2.5" Tip Size: 3.5"
    Muffler Type: Chambered Fitment: 05-09 V6 Mustangs
    Will it fit my Mustang?

      Customer Photos (52) Submit Your Photo

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        Questions & Answers (22)

        5 Top Rated Questions

        I bought my mustang with this already installed, is there a way to make it more aggressive and louder sounding without totally replacing it?

        • There is no way to modify the sound of the exhaust directly, other performance parts would have to be added to the vehicle to change the volume/tone.

        Helpful (0)

        Is there any Horsepower gained compared to a stock V6?

        • There really would not be any horsepower gain with these. At most you may see a gain of 1-2 horsepower.

        Helpful (0)

        My mustang is straight piped and I had a piece of pipe welded where my muffler used to be. Will I still be able to install this product?

        • A significant amount ofalteration would be needed to install this item due to your existing modifications. 

        Helpful (0)

        Will this muffler cause an emissions test failure?

        • This will not cause any emission test failures no.

        Helpful (0)

        I have a 2005 mustang and was wondering how do I install it??? Do I have to weld it??? Or what? Tia

        • The Flowmaster American Thunder Axle-Back Exhaust will simply clamp on to your exhaust. More details can be found in the install guide, linked below: https://lib.americanmuscle.com/files/18404-18419-40037-48021-29000-cust.pdf

        Helpful (0)
        10 More Questions
        How can I hear the actual sound of the Flowmaster American Thunder Axle-Back Exhaust on the 2005 to 2009 Mustang V6? Is there a video to hear from Flowmaster? Thanks. 1 answer
        Does this exhaust have an annoying drone sound to it or does it sound good while driving 1 answer
        It says the exhaust includes a hanger, I have a 2007 mustang and Im just changing the one exhaust to this , will I still need the hanger kit ? 1 answer
        Will this fit a 2004 V6? 1 answer
        Will this fit on a stock 05 mustang without any other items for it? I mean can it just go right on after taking off the stick muffler just as easy as that?? 1 answer
        I notice a great decrease in my horse power when I installed this piece. I like the noise it makes but it accelerates slow. How can I get my horse power back? Should I buy another pieces instead? 1 answer
        So I have this for 8 years now and really wanna convert to dual and still keep my old one ..my question can I buy just the other side (left side ) since I already have the right one thank you .. 1 answer
        If I instal the flow master exhaust on my 2005 v6, would I have to do a tune up for it?? Or what do I have to do? 1 answer
        How can I make this into a dual exhaust setup? Would an x-pipe work with this? 1 answer
        How well will this worth when i install long tube headers? 1 answer

          Customer Reviews (100+) Write a Review

          Overall Rating 4.8

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:0-$100

          • Loudness / Volume 4.348416 4.3
          • Exhaust Note 4.590909 4.6
          • Fit & Finish 4.692307 4.7
          • Bang For Your Buck 4.653153 4.7



          • 4/5

            Installation Time: Less than 1 Hour

            September 05, 2019

            Great tone but still a v6

            This exhaust sounds great and a must have. Adds a lot of volume and a lot of tone. Loud when you want it to be, or can sound stock. It does have a trumpet type sound occationally, usually right after a cold start. Sounds great but you’re not fooling anyone, sounds like a v6 not a v8.

            BentleyZ

            Year: 2006 Submodel: V6

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $100-$250

            March 22, 2019

            Awesome Muffler

            Just had this muffler installed on my 2005 mustang convertible v6. It sounds great! It has a nice deep sound to it. It's not real loud at idle but when you give it gas it's got great sound. It sounds similar to a v8. I usually do all the work on our cars but I just had surgery so I had a muffler shop do it. They charged me 120 which I think was overpriced.

            Brad

            Year: 2005 Submodel: V6

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            March 19, 2019

            Worth it!

            I was looking for something to spice up my car, that wouldn’t be an entire project. Found axel back exhausts and was intrigued. I watched tons of videos on the sound of each style, the installation, and comparison. I landed on the American Thunder from Flowmaster and I was not disappointed in the slightest. I love the way this has made my car sound. Completely stock, but it sounds so much better than the stock muffler it comes with. I highly recommend this.

            GoodTimes

            Year: 2005 Submodel: V6

            Helpful (0)

          • 4/5

            Installation Time: Less than 1 Hour

            January 27, 2019

            Flowmaster

            Muffler arrived quickly and and packed in foam, and supplied with a good quality clamp. Installation was easy and everything lined up well. Sounds good without excessive volume. Good product.

            JimM

            Year: 2006 Submodel: V6

            Helpful (1)

          • 4/5

            Installation Time: Less than 1 Hour

            January 10, 2019

            Great product.

            Installing this took no time at all. It sounds and looks great.

            AnthonyC

            Year: 2006 Submodel: V6

            Helpful (2)

          • 4/5

            Installation Time: Less than 1 Hour

            December 18, 2018

            I like it

            It has a nice sound. It’s not to pound when you’re idle. Reving has a very nice sound too.

            ChandaH

            Year: 2007 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            November 19, 2018

            Beautiful install!

            Installed in less than an hour. Love the sound flow it brings to my mustang.

            TywainH

            Year: 2008 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Afternoon

            October 25, 2018

            Very Satisfied

            I’ve had a Flowmaster exhaust on a previous vehicle I owned and know the quality, fit and finish of their products. This one did not disappoint. Now my V6 has that undeniable Flowmaster sound. I would highly recommend this product.

            AndreP

            Year: 2007 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            September 25, 2018

            Good sound

            Did not take long. Hardest part was removing the old muffler.

            JoshC

            Year: 2007 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            September 13, 2018

            Muffler

            Sounds great! Not too loud but loud enough to turn some heads...

            JuanJ

            Year: 2005 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            September 13, 2018

            Perfect sound!

            Was looking for just a bit more rumble down the roadways. This was the perfect mod for my pony! You will hear the difference between your factory install and this Flowmaster addition. GREAT PRICE and GREAT PRODUCT. Thank you once again AM for another quality mod for my ride.

            SusanM

            Year: 2006 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            August 04, 2018

            Awesome

            Great sound not too loud, have that deep sound of a muscle car

            JuanG

            Year: 2008 Submodel: V6

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            August 03, 2018

            Good exhaust

            Bought it for my v6 mustang . Helped complete the build and sounds great! 8/10

            JohnR

            Year: 2005 Submodel: V6

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            July 18, 2018

            Flowmaster American Thunder muffler

            Beautiful sound, perfect fit, easily install. Very happy with the quality of the muffler and the sound. Nice deep rich tone. Not quiet but not overpowering.

            DanielK

            Year: 2007 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Afternoon

            June 27, 2018

            Sounds great

            Car breathes much better than with the stock muffler and it's not annoyingly loud. Install is easy, taking the old muffler off was the hardest part.

            CaseyD

            Year: 2007 Submodel: V6

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            June 23, 2018

            Amazing

            Absolutely in love with this muffler, made my V6 sound so much nicer, getting praise from many people. Easy install, no problems whatsoever, came earlier than expected so that’s an added bonus

            FranciscoM

            Year: 2008 Submodel: V6

            Helpful (4)

          • 5/5

            Installation Time: Less than 1 Hour

            April 03, 2018

            Good sound

            Just how it should sound.a must mod! Sound not to quiet or loud, just right.

            FrankC

            Year: 2008 Submodel: V6

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            February 28, 2018

            Muffler upgrade

            This is the perfect muffler for the V6 motor , if your wanting to stay with the factor single exhaust that comes on the mustang, gives you that deep sound of the bigger motor without changing anything else

            RandyB

            Year: 2006 Submodel: V6

            Helpful (6)

          • 3/5

            Installation Time: Less than 1 Hour

            February 06, 2018

            Its ok

            I had this muffler for about a year but then I a muffler delete by just welding on a new pipe to replace the muffler which only cost me 80$. 10x louder than the Flowmaster but if you don't want to go too loud I would recommend this

            Jessie

            Year: 2006 Submodel: V6

            Helpful (3)

          • 4/5

            Installation Time: Less than 1 Hour

            February 05, 2018

            American thunder

            When I received the muffler the paint was scratched a little over an inch. Went to install and looks a bit crooked because the arm on it. Wasn’t as loud as a GT but over all I’m pleased.

            DennisF

            Year: 2007 Submodel: V6

            Helpful (4)

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