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

Market Price $509.99 You Save 13% ($67.02)
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$442.97

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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?
    • Boss 302 - 12
    • GT - 11, 12
    • GT500 - 11, 12

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    Customer Photos (22) Submit Your Photo

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    15 Questions / 8 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)

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    Customer Reviews (100+) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:0-$100

    • Loudness / Volume 4.857143 4.9
    • Exhaust Note 4.871428 4.9
    • Fit & Finish 4.671429 4.7
    • Bang For Your Buck 4.828571 4.8



    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 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 (0)

    • 5/5

      Installation Time: Less than 1 Hour

      July 14, 2017

      Worth the price.

      Ordered these to my dads shop, they arrived on time and in great shape. Install was easy, you just have to mess with the stock exhaust to jar them lose. Awesome sound, powerful roar when I accelerate and the burble pop when you let off the gas. Truly awesome sound and quality

      KennethG

      Year: 2011 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      July 13, 2017

      Made my BOSS sound like a Boss.

      Easy install, perfect fit and the finish was flawless. And let's not forget the added volume; this thing is just plain mean. There's a little drone at 2000rpm, under throttle, but it's worth it to finally hear my 302 sound the way it should.

      Logan

      Year: 2012 Submodel: Boss

      Helpful (0)

    • 5/5

      Installation Time: Afternoon

      July 04, 2017

      Unbelievable Sound

      I have a Boss 302 with the side pipes completely open and with these mufflers on cold start it sounds like a stock car. After it warms up its still loud but not as loud. Sound is still louder than the Ford Performance mufflers. Install wasn't to bad but a little harder than i've read on here. Undoing the clamps was the easiest for me. Getting the mufflers off the hangers was a pain. I pushed the muffler toward the front the the vehicle and was able to get them off the front hangers, then it was easy to remove the rear. For installing, on the driver side, I losened all three hanger bolts and removed the one toward the front of the car. Same with passenger side except it only has two bolts. I would say uninstall/install was about 2 hours. In the end, it was well worth it for the sound!

      JohnK

      Year: 2012 Submodel: Boss

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      June 29, 2017

      Great sounding

      Easy to install. Looks better than factory. Sounds amazing.

      BenP

      Year: 2012 Submodel: GT

      Helpful (0)

    • 4/5

      Installation Time: Less than 1 Hour

      June 15, 2017

      Awesome sound

      These mufflers really make the '11 GT sound like a beast. Everyone notices-usually good but not always. I had one neighbor who sleeps in the day ask if we could take it easy while going by his house. If you don't like the muscle car sound this isn't for you. My son also had the resonators removed. We did the install but had a small exhaust leak and ended up having them welded at a muffler shop.

      EvanJ

      Year: 2011 Submodel: GT

      Helpful (0)

    • 5/5

      April 30, 2017

      2011 5.0

      They sound amazing! Was a great install, easy and fit nice.

      jwayne71

      Year: 2011 Submodel: GT

      Helpful (0)

    • 4/5

      Installation Time: Less than 1 Hour

      April 04, 2017

      Sound matches look

      The sound of these axle-backs is better than listening to the radio... except at 2,000 rpm. At 2K rpm, the noise is not pleasant at all. But above or below 2K, its great. Easier to install than to get the original exhausts off. I am noticing better mpg. Maybe the flow-thru and the much less weight of the new system.

      RonB

      Year: 2012 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      March 22, 2017

      Flow master outlaws

      Absolutely amazing sound quality, match this with an off road x-pipe and you will have yourself an outstanding exhaust system.

      SteveC

      Year: 2011 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      March 10, 2017

      Great product!

      I wanted my mustang to stand out when it came to sound as well as looks. I'm running bbk o/r x-pipe combined with Flowmaster Outlaw axle back and it is LOUD like I wanted but the flowmaster mufflers give it that badass tone you lose with strieght pipes. The pipes fit great and quality is on point. Regardless if your running a cat or not I would definitely recommend this product if your looking for an aggressive muscle car sound.

      N2011Stang

      Year: 2011 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      March 06, 2017

      Super loud

      They are super loud! And easy to install! If you like loud go for it! I love it!!!

      MustangGT

      Year: 2012 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      February 26, 2017

      Deep muscle car sound

      Sounds great, I would recommend this exaust slight drone at 2k but you're probaly not buying them to be quiet.

      Jacobloveshismustang

      Year: 2012 Submodel: GT

      Helpful (0)

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