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Flowmaster Outlaw Series Axle-Back Exhaust (15-18 EcoBoost)

Market Price $499.99 You Save 16% ($80.00)
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$419.99

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  • Item 525581A
  • MPN# 817713

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    Features, Videos & Details

    • Super Aggressive Flowmaster Outlaw Sound
    • Durable 409 Stainless Steel Construction
    • 2.5" Mandrel-Bent Tubing
    • 4" Polished Stainless Steel Tips
    • Includes Two Flowmaster Outlaw Mufflers
    • Fits 2015-2018 EcoBoost Mustangs

    Review & Installation Video

    Justin: What's up, everybody? Justin with americanmuscle.com. I have Angelo in here with me today. He brought his brand new 2015 EcoBoost. We understand this isn't your first Mustang. Obviously, you have a little history with the Mustang. Tell us a little bit about it. Angelo: Yeah. Before the 2015, I had 2 Mustangs. I had a 2008 GT California Special. That was supercharged, Paxton NOVI 2200, Ford racing hot rod cams, and some Kooks long tubes. Justin: Very cool. Angelo: I also had a 2014 GT Track Pack, basic bolt-ons, nothing too crazy. Justin: How are you enjoying the new EcoBoost? Angelo: Definitely can't complain. The gas mileage has been awesome and it still has all the fun. It's an incredibly balanced car to have some fun on the street. Justin: That's what I like to talk about. We understand you like to do some events. I know you were talking to me about that. You love doing some solo stuff, some autocrossing. You've got to be loving the IRS. Angelo: It's a much better package out of the box than I expected, to be completely honest. Justin: Okay. As always, there's always room to improve. That's why you're here with us today. What are you looking for out of the car? Angelo: I'm looking to improve the ride height a little bit and stiffen it. Get a little of that brake dive out of there. Improve the body roll. Have it a little more predictable while I'm having some fun with it. Justin: It's probably a little quiet I'd imagine, right? We heard these stock EcoBoosts before. Angelo: Yeah. Justin: It's a fine line. You don't want to go too loud with the four cylinder, but I think we have something for you that might help you out. Angelo: Awesome. Justin: We definitely have something for the suspension that you helped us pick out. We're going to get you out of here. We're going to get to work on it. Then, we'll bring you back in and see what you think. All right, guys. We're getting started here with Angelo's EcoBoost. Angelo is a self proclaimed road racer. He's done some autocross stuff in the past. Therefore, he's very familiar with Eibach, as most of us are. He really wanted to go with the pro-kit here. The pro-kit is the milder of the two options from Eibach, the other one being the sport line which do drop the car a little more. The pro-kit is going to drop his Eco boost just over an inch up front and an inch in the rear, getting rid of that wheel gap, lowering the center of gravity, and really helping his cornering in the process. Guys, with any spring install, of course, you're going to need your spring compressor here. We've got ourselves a nice one. It makes the job a heck of a lot easier. Trust me. We already got the other side installed, so we're just going to finish up here with the driver side and then move to the rear. With the car still up in the air, we have a couple more performance parts we're going to do. Let's do the exhaust first. Guys, just wrapping up the axle-back here with Angelo's EcoBoost. He wanted the Flowmaster Outlaw series axle-back for now. Definitely looking for a little bit more performance. A little bit more sound is going to be a given here with this exhaust. It is an axle-back with the 2015, so you do have to cut. As long as you make the right measurements and make a good cut with the Sawzall, you should have it up and in no problem in about an hour I'd say. All right, guys, I'm a fan of starting with the hardest stuff first, the springs in that case, and then working towards the easier stuff, which in this case, is this brand new Airaid cold air intake that Angelo's getting for his EcoBoost. The Airaid is a great product. With these 2015 EcoBoosts, it's a no tune required intake. It shouldn't take any longer than 30 minutes to throw on. We'll get it on, get Angelo in here, and see what he thinks. What do you think of the ride height? Angelo: That's exactly what I was hoping for. Justin: Yeah? Nailed it, huh? Angelo: The ride height is perfect. It has just a little bit of rake. The front's a little bit lower. Got rid of that lifted front end it had from the factory. Justin: Absolutely. I love the pro-kit, too, because of that. A lot of the springs level it out. The pro-kit drops a little bit more in the front as you pointed out. I think it really is a perfect stance. Angelo: Definitely. Justin: Well, Angelo, before we set you loose on the roads, man, obviously we've got the car all go pro up here. Why don't you fire this thing up and let's hear how that Flowmaster sounds. Angelo: Yeah, let's do it. Justin: Okay, nice. Nice, man. Angelo: Definitely more refined than I was expecting for the EcoBoost. Justin: I'm with you, man. It's definitely not obnoxious whatsoever. It actually sounds really good. You get a little turbo noise through there. Angelo: Yeah. Justin: You happy with it? Angelo: Absolutely, that's exactly what I was hoping for. Justin: Very cool. Let's get you out on the roads here. You can tear it up and let us know what you think. Angelo: All right. Let's see how this exhaust sounds here. Oh yeah, nice little crackle out the end. That sounds perfect. Definitely a huge step up from the stock muffler, but still refined. Springs are definitely comfortable. Not too stiff, but definitely has a lot more control. Alot less brake dive. Springs feel perfect on the corners. Much more predictable. That blow off valve is a lot louder than I expected. The intake definitely helped out with the throttle response. It seems like I barely need to give it gas for that turbo to respond. It's crazy how much you can get out of three simple mods. Justin: Angelo, you just got done blasting around in the EcoBoost with all the mods. What do you think so far, man? Angelo: I think it's exactly what I was hoping for out of this package. It's got a balanced suspension. It's got a nice note out of the exhaust. And, I can hear the turbo on a little of that diverter valve. Justin: There you go, man. Thanks so much for bring the car by, brother. Angelo: Thank you. Justin: We really appreciate it. I know you're not done with this thing, so maybe as you'll want to do some more mods, you'll bring it through. Angelo: Sounds good. Justin: All right, man. Thanks for watching guys, and for all things Mustang, keep it right here at americanmuscle.com.

    Super Aggressive Flowmaster Sound. Give your EcoBoost 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 2.5" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties, the Flowmaster Outlaw Axle-Back features (2) 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.

    Cut & Clamp Installation. The installation of this Axle-Back Exhaust requires cutting and removing the stock muffler assemblies, and clamping the new muffler assemblies in place. Clamps and instructions are provided.

    Application. This Flowmaster Outlaw Series Axle-Back exhaust system is designed to fit the 2015-2018 EcoBoost Mustangs for both great looks and great sound.

    Fitment: 2015 2016 2017 2018 Details

    What's in the Box
    • (2) Muffler Assemblies
    Installation Info
    Tech Specs
    Axle-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
    Piping Size: 2.5" Tip Size: 4.0"
    Muffler Type: Straight-through Fitment: 2015-2017 EcoBoost
    Will it fit my Mustang?
    • EcoBoost - 15, 16, 17, 18

    People Who Bought This Item Also Bought

    Most Helpful Reviews

    5/5
    I highly recommend

    I was a little leery at first, afraid my mustang could sound like one of those little foreign cars with a whining exhaust. There simply is no sound that can replicate the rumble of a V8, BUT this was ...

    Read More
    Helpful (11)

    5/5
    Buy. This. Exhaust.

    First off AM has the BEST service and shipping. Period. For those who believe that a turbo 4 can't sound deep and smooth I invite you to listen to this product in real life. Microphones cannot capture ...

    Read More
    Helpful (6)

    Overall Rating 4.8 out of 5 stars
    Read All 100+ Reviews

    Customer Photos (10) Submit Your Photo

    View All 10 Photos

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    41 Questions / 6 Answers

    Ask a Question

    is this product legal in the Rio Grande Valley ,Texas

    reys

    • Unfortunately, we are not familiar with the local laws and regulations in your city. Please contact your local Department of Transportation, and/or Law Enforcement Agency.

      VincentV

    Helpful (1)

    I have the convertible version of the 2015 Mustang Ecoboost Premium. With this axle-back fit?

    JPS04001

    • The Flowmaster Outlaw Series Axle-Back Exhaust is designed to fit both coupe and convertible ecoboost Mustangs.

      Rob D

    Helpful (1)

    I live in California. If i put this on, will i still pass smog? This is probably the only reason holding me back. I have a 2017 v6 mustang.

    Daniel

    • The Flowmaster axle backs will pass smog testing however you will want to check your local laws on noise restraints to be safe.

      Ricky36

    Helpful (1)

    Is it absolutely necessary to cut and bolt on or can I get away with not cutting at all?

    Mustapha08

    • Hello! Yes, the installation of this Axle-Back Exhaust requires cutting and removing the stock muffler assemblies, and clamping the new muffler assemblies in place. Because this exhaust starts where there is no section to unbolt you will have to cut and slip it into the existing piping coming out of the muffler.

      Ryan H

    Helpful (1)

    I live in California and was wondering if this exhaust system is CARB certified. Would it pass smog check if I install it on my car?

    Dave

    • The Flowmaster Outlaw Series Axle-Back Exhaust is CARB legal since it does not affect the catalytic converters. The only issue you could face is that this exhaust is one of the louder ones. Research your local noise ordinances to make sure the sound level of this exhaust would be legal in your area.

      pserafi

    Helpful (1)

    How much horsepower will this add to my 2015 mustang ecoboost?

    Daniel

    • Generally axle-back exhausts only increase sound and do not provide any horsepower gains.

      AMJustin

    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:$100-$250

    • Loudness / Volume 4.522124 4.5
    • Exhaust Note 4.637168 4.6
    • Fit & Finish 4.840708 4.8
    • Bang For Your Buck 4.769911 4.8



    • 5/5

      Installation Time: Less than 1 Hour

      March 19, 2017

      I highly recommend

      I was a little leery at first, afraid my mustang could sound like one of those little foreign cars with a whining exhaust. There simply is no sound that can replicate the rumble of a V8, BUT this was well worth the money. It completely changed the sound of the car....for the better. Inside, it has a very nice deep tone but not too loud at all. Actually, it only is loud when you really open it up and the turbo kicks in. At that point, honestly it sounds awesome. I could not be more pleased both with the sound and the looks. As usual, American Muscle shipped it out asap. I highly recommend. 2017 Mustang Ecoboost

      DavidT

      Year: 2017 Submodel: EcoBoost

      Helpful (11)

    • 5/5

      Installation Time: Shop Install

      April 08, 2017

      Buy. This. Exhaust.

      First off AM has the BEST service and shipping. Period. For those who believe that a turbo 4 can't sound deep and smooth I invite you to listen to this product in real life. Microphones cannot capture the low rpm rumble or the mid range howl. That's with no other mods. Don't wonder. Just buy it.

      GabrielB

      Year: 2015 Submodel: EcoBoost

      Helpful (6)

    • 5/5

      Installation Time: Less than 1 Hour

      June 07, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      This with an Xpipe/Resonator Delete is great

      I want to clarify I have this and a resonator delete (aka an Xpipe). On cold starts sounds great and is loud but when its warm idling its not annoying. Drones alittle on the highway but nothing really annoying. I cruise with the radio at like 10-15 and you dont notice it really. If youre only installing this there shouldnt be an drone. Makes the V6 sound great. Its no GT but its a great sound nonetheless.

      BrandonL

      Year: 2017 Submodel: V6

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      April 27, 2017

      They rock!!!!

      Very good product and easy to install, videos don't do justice on how they sound and it's how the advertisement say is very loud when u get on but suttle under normal driving. Once broken in they are not as loud as the first time u get them on. Very satisfied.

      AbelA

      Year: 2015 Submodel: EcoBoost

      Helpful (4)

    • 4/5

      Installation Time: Less than 1 Hour

      April 25, 2017

      Good sounding exhaust!

      Shipping was fast. Had a local shop put it on for $80. Seems kind of quiet at first but after driving around for a week I feel like it got louder. Nice deep rumble at low RPM is exactly what I wanted. Noticed a little power gain too. If you're looking for a nice exhaust for cheap this is the way to go.

      VLAD702

      Year: 2017 Submodel: EcoBoost

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      April 17, 2017

      Amazing!

      I am more than satisfied with my product, it overpasses my expectations by a lot. Easy install, fast shipping, reasonable price. What more can you ask for?

      OsvaldoC

      Year: 2016 Submodel: V6

      Helpful (4)

    • 4/5

      Installation Time: Less than 1 Hour

      March 24, 2017

      Outperformed my expectations

      Received my exhaust system right on time as expected and jumped right in. With a jack, two jackstands, a harbor freight saw, and two sockets, my new system was up and running in about 45minutes to an hour. Super simple install, and my god, they are loud, and they have a sweet spot around 4k rpms where it just snap, crackle, pops. Above 4k it still sounds great, but gets slightly raspy, but for my ecoboost it far and away exceeded my hopes and expectations. I am very satisfied with this mod!

      KevinT

      Year: 2015 Submodel: EcoBoost

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      July 18, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Must have

      Changes stock sound completely, had it on for almost 4 months now, although I'm gonna add the X-pipe as well as the bbk shorty's

      JesseM

      Year: 2017 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      May 30, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Loud

      If loud is what you are looking for. This is the product for you.

      JasonR

      Year: 2016 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      May 04, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      WORTH IT!

      I honestly love the sound this gives to my car. It's not a V8 and it never will be, but this is my car and I love everything I've done to it! The exhaust definitely gives it a more deep tone and really makes you feel like you're driving a mustang. It really is an amazing Mod, I don't know why I didn't do it sooner! Had it installed by Ford so my warranties won't be voided, way worth it. peace of mind and an awesome sound!

      Rush

      Year: 2016 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      April 29, 2017

      Awesome sound!

      Great sound and great quality. As always American Muscle was quick to deliver. Installing this axle back was simple, I installed it in my garage with the car backed up on ramps. Few days after purchasing this exhaust i a did a resonator delete Y-Pipe. Everyone compliments the sound of my car.

      Clay

      Year: 2017 Submodel: EcoBoost

      Helpful (3)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      March 28, 2017

      Sounds good

      I bought these for my 16 Ecoboost to give it a little more sound, and it sounds so good! It's pretty deep and quiet at normal cruising sounds. It's loud when you want it to be. Worth the money.

      Edson

      Year: 2016 Submodel: EcoBoost

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      March 15, 2017

      Great addition to my 2015 EcoBoost Mustang

      I wanted to improve the exhaust sound for my 2015 EcoBoost Mustang and the Flowmaster Axle-Back delivered. Installation instructions were easy to follow. The installation took me about 2 hours. I love the improvement in sound and tone of the exhaust.

      DavidV

      Year: 2015 Submodel: EcoBoost

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      May 08, 2017

      Wake up

      The flowmaster outlaw axle back is really great quality, fast shipping from American muscle, and the ecoboost sounds amazing. It is loud but more refined then I expected it to be, 4,000 rpm is the sweet spot, awesome buy and definitely will come back to American muscle for more products. 100$ install cost

      IsaacM

      Year: 2017 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: 0-$100

      April 27, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Perfect!!

      Bought this exhaust after doing alot of research on all my options. I couldn't be more pleased with this exhaust, it sounds perfect! You cant beat the price either! Only costed me $50 per side for the install. You will love this exhaust.

      Zman918

      Year: 2015 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      December 18, 2017

      This exhaust is awesome

      I think the least money gets the best.Just buy it, trust me!

      HuilongX

      Year: 2017 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      July 01, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Great quality

      Looks great. Haven't installed yet but overall happy with the quality of the product.

      Luis

      Year: 2016 Submodel: V6

      Helpful (1)

    • 3/5

      Installation Time: Less than 1 Hour

      June 29, 2017

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      It's okay

      Was expecting it to be louder. Easy to install. Not sure if it's worth as much as it cost. Has a low baritone sound.

      Cristian

      Year: 2016 Submodel: V6

      Helpful (1)

    • 5/5

      June 22, 2017

      Dope

      Super throaty changed the whole style of the car! Easy install and sleek appearance.

      KingBlue

      Year: 2016 Submodel: EcoBoost

      Helpful (1)

    • 4/5

      Installation Time: Less than 1 Hour

      June 18, 2017

      Great Choice

      The axle back exhaust system is amazing, definitely upgraded the sound of my ecoboost a very deep growl but not obnoxiously loud. Sounds great on a cold start and when you are on the gas but quiet at idol

      Colton

      Year: 2016 Submodel: EcoBoost

      Helpful (1)

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