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Flowmaster Outlaw Series Axle-Back Exhaust (11-12 GT, GT500)

Market Price $516.99 You Save 12% ($59.51)
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$457.48

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  • Item 18422
  • MPN# 817516

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    Features, Video & Details

    • Super Aggressive Flowmaster Outlaw Sound
    • Durable 409 Stainless Steel Construction
    • 2.75" Mandrel-Bent Tubing
    • 4" Polished Stainless Steel Tips
    • Includes Two Flowmaster Outlaw Mufflers
    • Fits 2011-2012 GT, Boss and 11-12 Shelby GT500

    Review & Installation Video

    Review & Install Video

    Hi I’m Justin with AmericanMuscle.com, and I’m taking a look at Flowmaster’s outlaw series axle back for your 2011 and up Mustang GT. The outlaw series is Flowmaster’s most aggressive system thanks in part to the straight through, race oriented style mufflers. The result, a super aggressive tone that’s sure to get you noticed. The system is constructed from durable 2 and 3 quarter inch 16-gauge steel, leading straight through these outlaw style mufflers. The cheery on top are these 4 inch polished tips, embellished with a Flowmaster logo. A simple bolt on installation here guys, should take you no more than an hour. Let’s hear how Flowmaster’s outlaw style axle back measure up to the stock exhaust.

    Super Aggressive Flowmaster Sound. Give your Coyote powered Mustang that unmistakable Flowmaster sound with the Outlaw Series Axle-back exhaust system from AmericanMuscle. This system improves exhaust flow using Flowmaster's race-oriented style Outlaw mufflers for that super, aggressive exhaust note your high powered Pony deserves.

    Stainless Steel Construction. Constructed from durable 2.75" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties the Flowmaster Outlaw Axle-back features two race-oriented mufflers with massive 4.0" diameter polished stainless steel tips for impressive muscle car looks and sound. As an added bonus the tips are embossed with the "Flowmaster" logo for true custom styling.

    Application. This Flowmaster Outlaw Series Axle-back exhaust system is designed to fit the 2011-2012 GT, Boss and the 2011-2012 Shelby GT500 Mustangs for both great looks and great sound.

    Fitment: 2011 2012 Details

    What's in the Box
    • (2) Muffler assemblies
    • (2) 3/8" Hanger Keepers
    Installation Info
    Tech Specs
    Axle-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
    Piping Size: 2.75" Tip Size: 4.0"
    Muffler Type: Straight-through Fitment: 2011-2012 GT, Boss and Shelby GT500
    Will it fit my Mustang?

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    15 Questions / 34 Answers

    Ask a Question

    How far does the tips extend out the rear of the car? I was wondering how far does the tips extend out the rear of the car compared to stock?

    Silverghost40

    • Not much at all it's perfect

      Stangbang

    Show 1 more answer Helpful (1)

    If I get the pypes true dual conversion for my 2010 V6, will this axel-back fit?

    AllisonB

    • I do apologize, but this Flowmaster Outlaw Series Axle-Back Exhaust will not work with the Pypes True Dual Exhaust X-pipe Kit. You would need to use item number 18423 which you can find here: https://www.americanmuscle.com/flowmaster-outlaw-axleback-0510gt.html

      pserafi

    Helpful (0)

    Will this fit on a 2011 V6?

    Jay

    • This Flowmaster Outlaw Series Axle-Back Exhaust is designed to fit the 2011-2012 GT, Boss and the 2011-2012 Shelby GT500 Mustangs only.

      Ricky36

    Helpful (0)

    If I get the right pipes on my 2010 mustang will I beable to just put this exhaust right on?

    AllisonB

    • The Flowmaster Outlaw Series Axle-Back Exhaust will not work on your car as they are for 11-12. However, with the mid-pipe, I have linked below you will be able to then put any 05-10 GT cat-back on your car. https://www.americanmuscle.com/pypes-0509-v6-xpipe.html

      Ricky36

    Helpful (0)

    What is the difference between these and the 13-14 model. Would the 13-14 not fit a 2012 Boss

    Matt05GT

    • The rear lower valance on the 2013-2014 models is different from that on the 2011-2012 model Mustangs. These are specific for the 2011-2012 model Mustang rear end.

      KevinD92

    Helpful (0)

    do you have to make computer adjustments after installation

    streetkidmitch

    • No. I have them on my 2011 GT500 and they sound great. If you have it mapped you wil probably pick up a few more horsepower but they're good on their own.

      GT500Frank

    Show 1 more answer Helpful (0)

    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 4.86755 4.9
    • Exhaust Note 4.880795 4.9
    • Fit & Finish 4.675497 4.7
    • Bang For Your Buck 4.834437 4.8



    • 5/5

      Installation Time: Less than 1 Hour

      June 22, 2018

      Bad to the bone!

      These axle backs are so impressive it’s more than I expected! The sound and the tone these produce are amazing and don’t hold back to pull the trigger on these outlaws!

      Junior

      Year: 2011 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      May 28, 2018

      Bada**

      I’ve got my flowmaster outlaws paired with bbk long tube headers and a bbk off-road x-pipe and it is insanely loud and has a great tone. Sounds like a dragcar when you get on it and I love it!

      MattR

      Year: 2011 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      May 12, 2018

      The love of my car life.

      These exhaust are the best on the market. The coyote engine sounded like a quiet person at the library with the stock mufflers. Now with the Flowmaster Outlaws on my Mustang the coyote does more than howling it growls and roars.

      SladeOutlaw

      Year: 2012 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 12, 2018

      Love it!

      The axle back itself was a easy install only reason it took so long for me and my dad was the cat delete pipes but those with a x pipe and outlaws my car is easily the loudest car on base (military) some might think it’s too loud but they are outlaws for a reason ;)

      CameronT

      Year: 2012 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 10, 2018

      Epic

      These are loud and very aggressive. You are definitely going to bring attention to yourself but the second are worth it if that's what your looking for.the install was also really easy it took me 45 minutes to complete.

      ReginaldS

      Year: 2012 Submodel: GT

      Helpful (3)

    • 5/5

      May 10, 2018

      AWESOME!!!!!

      Love the Flowmaster Outlaws!!!!! Definitely recommend for anybody with a GT.

      NathanaelA

      Year: 2011 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 04, 2018

      Sounds amazing!

      Mufflers were very well packaged with extra protection on the tips also shipping was spot on as for the mufflers I had a resonator delete done just before I installed them and the sound quality is above and beyond what I thought it would be! Worth every dollar

      BrianM

      Year: 2012 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      April 24, 2018

      Master of sound

      I had to cut my old exhaust off and get new claps cuz of rust but after that it was easy and o my god the sound is a 10 out of a 10 just for an axle back too

      CameronD

      Year: 2012 Submodel: GT

      Helpful (3)

    • 5/5

      April 19, 2018

      Good stuff

      Good fitmet , sounds good. Took about an hour to do both sides .

      MattO

      Year: 2011 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      March 08, 2018

      Loud muscle

      For everyone that wants to makes your Mustang sound like a muscle car all day every day this is the exhaust of choice. I love the how light these outlaws are comparable to the stock exhaust. You are able to hear the car idle and the feeling of pressing the gas from a stopped position makes it worth it each time.

      AaronG

      Year: 2012 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Afternoon

      March 05, 2018

      Straight Up BAD

      This exhaust set up is very aggressive and really brings out the sound of the coyote horsepower! Highly recommend. One slight issue we faced was the pipes at the ring clamp were basically unmovable due to rust and time... had to torch them to get heated up and then they removed easily.

      Jeff

      Year: 2011 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      January 23, 2018

      Pretty good.

      Ordered these hoping they’d be a bit louder but nonetheless they seriously improved the exhaust note. Slight drone at highway speeds but it was made to be heard. Installed these in less that 45 mins with the hardest part only being removing the stock mufflers from the hangers. Simple install. Very happy with the product.

      BlackWidowStang

      Year: 2011 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      December 17, 2017

      Amazing

      Could not be happier with these. Great sound, not just stupid loud. For sure a head turner.

      ReeseG

      Year: 2012 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      December 12, 2017

      Axel Backs

      My neighbor loves the sound of these. They are 4 house down from me. :)

      john

      Year: 2011 Submodel: GT

      Helpful (6)

    • 5/5

      Installation Time: Less than 1 Hour

      December 11, 2017

      Outlaws

      I purchased the Flowmaster Outlaws for my 2011 5.0 and I am very pleased with the system. Great quality and the is sound awesome.

      Sandra

      Year: 2011 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      December 01, 2017

      Exhaust Install

      Easy to put on and sounds amazingly loud! My husband was in love with his gift.

      LindaM

      Year: 2011 Submodel: GT500

      Helpful (5)

    • 5/5

      Installation Time: Afternoon

      September 06, 2017

      Keep in mind

      There are a few things you want to keep in mind when buying this product. The biggest is the drone. If you like loud and aggressive and really want to upset the neighbors then go for it. I personally don't mind it at all but I've ran into quite a few who do. Also the installation process will go much quicker if you have a professional jack to lift the car into the air. Otherwise you'll be underneath the car fighting with the hangers depending on how old the car is. I have a 12 and the hangers were no very complying when attempting to remove the stock muffler. Overall the sound is absolutely amazing, but be prepared to have a drone at about 70mph on the highway at 2-2100 rpms....and it won't go away.

      SethL

      Year: 2012 Submodel: GT

      Helpful (5)

    • 2/5

      Installation Time: Less than 1 Hour

      August 23, 2017

      Uneven tips

      Sound is great. Install was easy. The right tip was not even and drain hole was to the left and the left tip was not as bad and drain hole to the left. Customer service said to take it to a shop and have new tips installed and I maybe able to get some money back. In the past no issue they would send out new parts and I would send back the damage. Done deal. Also sent them photos.

      FF014

      Year: 2012 Submodel: GT500

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      August 16, 2017

      loud

      these thing are loud, I love them. I have always been a flowmaster, they did not let me down, they rock.

      RodrickR

      Year: 2012 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      August 14, 2017

      Flowmaster Outlaw Series on a 2012 Shelby GT500

      Incredible sound compared to the Magnaflow exhaust that was on it. It's aggressive, mean and sounds the way a powerful American muscle car should! Easy 5-Star rating.

      SportPilot

      Year: 2012 Submodel: GT500

      Helpful (5)

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