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SLP Loudmouth Axle-Back Exhaust (11-14 GT; 11-12 GT500)

Market Price $439.95 You Save 4% ($17.00)
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$422.95

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  • Item 23042
  • MPN# M31023

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    Features, Video & Details

    • Rich, Throaty Exhaust Sound
    • Muffler Delete
    • 2.5" Mandrel-Bent 409 Stainless Steel Tubing
    • 4" Polished 304 Stainless Steel Tips
    • Emissions Legal in All 50 States
    • Fits 2011-2014 GT and GT500 Mustangs

    Review & Installation Video

    Review & Install Video

    Hey what’s up everyone I’m Justin from AmericanMuscle.com, and I’m bringing you SLP’s loudmouth axle-back exhaust, for your 2011 and up GT Mustang. This loudmouth system eliminates the restrictive factory mufflers, which allows for more horsepower, it also makes for one mean exhaust note as well. The system is constructed from 3 inch mandrel bent stainless steel tubing, exiting through hand polished 4 inch tips, which result in a very clean finish. Simple bolt on installation, should only take you about an hour. Let’s hear how SLP’s loudmouth axle-back compares to your factory exhaust.



    Aggressive Throaty Exhaust Note. This SLP Performance Parts Axle-Back kit eliminates the restrictive stock mufflers from the 2011-2014 GT or GT500, drastically reducing back pressure to enhance power and to produce one of the most aggressive exhaust notes possible with the factory catalytic converters still installed.

    409 Stainless Steel. SLP's Loud Mouth axle-back system is made from 2.5" mandrel-bent 409 stainless steel tubing, which has excellent flow characteristics and features pre-welded hangers for simple installation. The hand polished, 4" dual wall tips give a show quality muscle car appearance to the rear of your Pony.

    Application. Made as a direct bolt on, this SLP Loudmouth Axle-Back bolts right up in the stock location without any modifications required on the 2011-2014 GT or GT500 Mustangs.

    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: 2011 2012 2013 2014 Details

    What's in the Box
    Hardware included: Hardware Included
    • (2) Clamps
    Installation Info
    Tech Specs
    Axle-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished 304 Stainless Steel
    Piping Size: 2.5" Tip Size: 4"
    Muffler Type: None Fitment: 2011-2014 GT and GT500 Mustangs
    Will it fit my Mustang?

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    13 Questions / 17 Answers

    Ask a Question

    Looking for a deep tone exhaust for my 2013 coyote. I’m installing long tube headers and off rd xpipe no cats. It will be more of a race car but I’m also looking to be able to use as a weekend car. Any recommendations ? Just don’t want exhaust to be overally load where I’m getting pulled over. But at same time don’t want to be quite either. Thanks

    GioI

    Will this work with the LTH Over Axle Pipes (11-14 GT, GT500)?

    ReeseG

    • The LTH over axle pipes have a diameter of 2.75" whereas the SLP Loudmouth axleback exhaust has a 3" pipe diameter. For these to work together you will need a 2.75" to 3" step up pipe modified for proper installation.

      KevinD92

    Helpful (0)

    Debating on these or flowmaster outlaw for my GT500 is their any back pressure in these or the flowmaster outlaws??

    Mark2010

    • There will not be any back pressure with these SLP Loudmouth's or with the Flowmaster Outlaws if they have been installed correctly.

      KevinD92

    Helpful (0)

    I have these and they drone way too much around 1.7k-3k, I heard I can buy a mid pipe and fix this issue. Can you guys recommend one for this problem

    FengG

    • Hello! We have many different options to take when looking at mid pipes, I would recommend that you look at one that is catted, if you are looking to quiet down the drone a little bit!

      Doug P

    Helpful (0)

    I'm stuck between getting the SLP or Flowmaster Outlaws. I want the one that has a real good tone to it and sounds like thunder clapping. is muffler deletion better? I'm leaning more towards the SLP but I need some help.

    Ilovemustangs97

    • What up I actually have the outlaws when i first had jus axleback the tone was great it was loud enough that u could be heard but not to much that its over baring but now i am full off road x pipes with cat deletes and lets jus say i have to stop driving to talk on the phone and i heard these slp in person im 25 im still young and i love the loud and wanna be louder but if u want to go over the top with loud go with the slp i warn u doe if u plan on goin cat less with a x/h pipe be ready to make ur neighbors mad

      dominique

    Helpful (0)

    Are the tips interchangeable. I want black tips and other than having them powder coated can these be changed out with black tips or no?

    daniels

    • You can change the tips since they are clamped on. As long as the ones you are going for are the same size, then you should not have any problems.

      AshleyK

    Helpful (0)

    People Who Bought This Item Also Bought

    Customer Reviews (89) Write a Review

    Overall Rating 4.6

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:0-$100

    • Loudness / Volume 4.786667 4.8
    • Exhaust Note 4.72973 4.7
    • Fit & Finish 4.493333 4.5
    • Bang For Your Buck 4.44 4.4



    • 5/5

      Installation Time: Less than 1 Hour

      July 04, 2018

      Insanely loud

      This exhaust makes me drive around with my windows down in July in Texas. Because hearing the car is worth the heat. Insanely loud. Definitely not for those trying to keep a low profile. Hope you're good at shifting if you have the 6 speed, because everyone's going to hear every detail of your shift. Goes from loud to just plain rude right around 3,000RPM.

      WyattH

      Year: 2013 Submodel: GT

      Helpful (0)

    • 4/5

      Installation Time: Less than 1 Hour

      July 04, 2018

      Mark

      Little louder than expected Drone inside at 2000 rpm or when under slight load at lower rpms. Simple to install. Didn’t need extra mounts that were recommended. Waste of money there. Overall good

      MarkK

      Year: 2014 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      June 29, 2018

      Axle-Back

      Best best exhaust I’ve ever bought worth every dollar!

      RicardoP

      Year: 2014 Submodel: GT

      Helpful (0)

    • 5/5

      June 03, 2018

      Let it rip!

      Wow!! One of the best mod I've had so far on my 2011 Shelby GT500 . I definitely recommend this product. Thank you AM.

      RJTINStang

      Year: 2011 Submodel: GT500

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      May 13, 2018

      Awesome

      Awesome exhaust. But if you see any cops be careful, I always hold the clutch in just in case passing by them. Overall it makes the mustang sound like a beast!

      NateH

      Year: 2011 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      May 07, 2018

      Slp loudmouth

      Excellent exhaust sounds nice!!! Really fast to install as well

      Ikexoxo

      Year: 2011 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      February 21, 2018

      2014

      Made my 2014 gt come to life with this slp loudmouths.

      VictorM

      Year: 2014 Submodel: GT

      Helpful (1)

    • 4/5

      February 19, 2018

      Sound Great, Drone on Highway

      These came on my car when I bought it and they sound great. I can still remember when the salesman started the car in front of me. They sound fantastic starting and accelerating. But cruising, mostly around 2k RPMs they drone like crazy. I just drove 17 hours cross country and I could still hear it over my audiobook. Music managed to conceal it nicely, though.

      LouisH

      Year: 2012 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      February 11, 2018

      Freaking great

      It is louder then I expected it to be but I enjoy it

      CodyC

      Year: 2011 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      February 03, 2018

      Way too loud (:

      I wanted my car to sound loud and these slp’s do the job!

      MathewS

      Year: 2013 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      December 08, 2017

      Great buy!!!!

      In my opinion this is the best sound on the coyote. Installation took an hour and adjustability was easy to get the tips just right.

      BLKCGR

      Year: 2011 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      October 13, 2017

      Badass pipes

      I put the SLP's on my 2012 mustang gt. I couldn't be happier , love the great sound compliments all the time , no droning running low rpm, the only thing when I installed them is that they only gave 2 clamps for the tips none for the flange had to use the old clamps from old mufflers, they worked ok ..

      AnthonyC

      Year: 2012 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      August 03, 2017

      SLP sounds amazing

      Absolutely love these from SLP the sound is amazing quality is spot on had no issue with the installation took about 45 mins start to finish. They really make the car sound great. Highly recommend to anyone looking for an exhaust upgrade.

      RyanM

      Year: 2014 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      August 01, 2017

      SLP Loudmouth

      The exhaust went on great, the only thing I wish I would have paid attention to is the factory exhaust clamps have to be reused, as I had to bugger them up a bit to get the factory mufflers off. Other than that everything fit great, and boy they sound GREAT!!! Night and day difference from stock. I would highly recommend this exhaust for any Mustang GT owner.

      CoreyL

      Year: 2011 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      June 16, 2017

      should have been factory

      mellow at idle and wild at wot. you wont be disappointed.

      1369

      Year: 2009 Submodel: GT500

      Helpful (2)

    • 3/5

      Installation Time: Less than 1 Hour

      April 08, 2017

      Not happy

      Was not what I expected. The video on here sounds completely different and louder. You can't even hear my car when I'm cruising at 30,40,50 or even 60mph. You can only hear it once you floor it. My old pype bombs were louder. Not impressed. Waste of 422$

      JoeA

      Year: 2014 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      March 01, 2017

      Awesome sounding exhaust!!

      I love the way it rumbles! Now all my 5.0 needs is some longtubes to be louder!

      Charliee

      Year: 2014 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      January 08, 2017

      Mean sound

      Stock headers and cats and still gives of a mean sound.

      Duke21

      Year: 2011 Submodel: GT500

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      December 29, 2016

      Doesn't Disappoint!

      Installed in about an hour. I think the tips could be a little larger diameter, but that is a minor request. The sound is amazing at full throttle. Still tame when driving responsibly. I don't have any drone at all either.

      CPP1

      Year: 2012 Submodel: GT500

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      November 22, 2016

      SOUNDS AMAZING also a tip for install

      I have a stock boss but these sound amazing. A bit of drone a 2k but anything over or under the drone goes away so just throttle control but drone doesnt bother me anyway. Installation of these was tricky but make sure you use a block of wood like it says in the instructions. Also the two rubber hangers here's a tip. Use your thumbs to push the rubber down far enough to get the rods in the rubber hole and definetly use WD40 on them.

      Chad

      Year: 2013 Submodel: Boss

      Helpful (1)

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