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

Market Price $297.99 You Save 12% ($34.31)
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$263.68

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  • Item 18404
  • MPN# 17421

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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

    CA Residents: Warning: California's Proposition 65

    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?

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    Customer Photos (52) Submit Your Photo

    View All 52 Photos

    Questions & Answers (20)

    5 Top Rated Questions

    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)

    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.

    • Flowmaster does have a video for their American Thunder Axle-Back Exhaust directly on their website, which I will link below: www.flowmastermufflers.com/exhaust-sytems/17421-axle-back-system-single-rear-exit-american-thunder-moderate-sound/

    Helpful (0)

    Does this exhaust have an annoying drone sound to it or does it sound good while driving

    • The Flowmaster American Thunder Axle-Back Exhaust will have some cabin noise. It will absolutely sound great on your 05-09 V6.

    Helpful (0)
    Post Your Question
    10 More Questions
    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
    How bad does this drone? And is this a better deal than just buying a whole dual conversion kit? 1 answer
    would the check engine light come on installing this? i know this is a dumb question but i just was wondering after installing this would i need to tune the car at all or would it cause the check engine light come on if i put this on? 2 answers

    People Who Bought This Item Also Bought

    Customer Reviews (100+) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:0-$100

    • Loudness / Volume 4.365741 4.4
    • Exhaust Note 4.595349 4.6
    • Fit & Finish 4.699074 4.7
    • Bang For Your Buck 4.657407 4.7



    • 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 (0)

    • 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 (0)

    • 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 (1)

    • 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 (0)

    • 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 (0)

    • 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 (1)

    • 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 (1)

    • 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 (0)

    • 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 (2)

    • 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 (3)

    • 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 (2)

    • 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 (4)

    • 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 (2)

    • 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 (3)

    • 5/5

      Installation Time: Less than 1 Hour

      January 24, 2018

      extra power plus american muscle sound

      very easy to install ,looks great and gives your v6 the sound of a true American muscle car.

      josephc

      Year: 2002 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      January 12, 2018

      Fantastic product

      Exactly what I was looking for. A very quiet ride when you're idling or going down residential roads, but picks up the noise when you turn the car on and when you hit around 3 rpm. It's nice to be loud when passing people, but not annoyingly loud at all times. Cabin is very quiet at all times. There's no rattle. It took about an hour to install. The chrome tip is a nice touch. It sticks far enough out the back where it is noticeable.

      BrianW

      Year: 2007 Submodel: V6

      Helpful (3)

    • 4/5

      Installation Time: Less than 1 Hour

      December 28, 2017

      Flowmaster American Thunder

      Installed on my 2006 with no issues, very straight forward. Start up sounds great and you can tell that it has a rumble. I read the reviews before purchasing about the fact that it did not have a drone and when you got on it the rumble came out closer to a V8. However, i have a convertible and can hear a drone between 1800 and 2200 rpm where mine likes to sit at cruising speed. I love it when under power but not sure if I am going to like turning up the radio a bunch much to overpower that drone.

      TimothyS

      Year: 2006 Submodel: V6

      Helpful (4)

    • 4/5

      Installation Time: Afternoon

      December 28, 2017

      Amazing Product

      Great product and not hard to install yourself. My only issue I’ve been having is a rattling coming from underneath that comes and goes as I adjust the clamp. Other than that this product is great. It’s loud, but not too loud.

      MattW

      Year: 2007 Submodel: V6

      Helpful (3)

    • 5/5

      November 15, 2017

      Perfect

      This is a perfect fit for my needs and what I was looking for in a single axle exhaust.

      MichelleB

      Year: 2009 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      November 01, 2017

      Solid replacement for your stock muffler

      I purchased this product because I wanted to have a louder, more aggressive sounding muffler. It is definitely much better sounding and louder than the stock muffler at idle and when you're on the gas. The sound you get is a deep throaty sound, not really a high pitched racey sound, so take that into consideration. The fit is okay, I know some say you have to bend the hangars, but mine went on fine. This muffler is on the lower end of loudness I'd say though. It's loud, but it could be louder, so if you're looking for something that's really, really, loud I'd say this isn't the one for you. It's quiet when you want it to be which is a plus, and also I like how it looks on the car. Overall, a solid replacement for your stock V6 muffler.

      JeffR

      Year: 2005 Submodel: V6

      Helpful (3)

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