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Flowmaster Outlaw Series Axle-Back Exhaust (15-17 GT)

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

$419.99

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  • Item 389966
  • MPN# 817732

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Features, Video & Details

  • Super Aggressive Flowmaster Outlaw Sound
  • Durable 409 Stainless Steel Construction
  • 3" Mandrel-Bent Tubing
  • 4" Polished Stainless Steel Tips
  • Includes Two Flowmaster Outlaw Mufflers
  • Compatible with Fastback and Convertibles
  • Fits 2015-2017 GT Mustangs

Review & Installation Video

Review & Install Video

Hey everyone, I'm Justin with americanmuscle.com. I'm going to be taking a closer look at the Flowmaster Outlaw series axle-back available for your 2015 GT Mustang. Flowmaster is, without a doubt, one of the most recognizable names in the world of Mustang and muscle car exhaust in general. In fact, we used several different Flowmaster systems on some of our past project car builds, including project Terminator. If you guys haven't seen these builds yet, what are you waiting for? Be sure to subscribe to our YouTube channel American Muscle Videos for the best Mustang specific content and product overviews available on the web. If you happen to be looking for one of the most aggressive axle-backs available for your Coyote powered S550, well then look no further than the Flowmaster Outlaw series. As you can see, this particular system does feature Flowmaster's patented Outlaw series mufflers which are the smallest and lightest muffler they offer and was originally designed for circle track applications where strict decibel sound limits had to be met with open header cars. As a result, Flowmaster designed those Outlaw series mufflers to be a straight-through free flowing design muffler, if you can really call it that, that will still offer plenty of sound. Picking up this system, I can tell you it is one of thr lighter systems I felt for the 2015 Mustangs. A lot of that can be attributed to those Outlaw series mufflers I just talked about in addition to the 409 grade stainless steel construction throughout. Finally, looking at the four inch polished tips here embossed with that iconic Flowmaster logo that will really help set off the rear of the car. If you guys aren't satisfied with this video and you want to see more detailed info on this exhaust, including more pictures and install tips, well then click on the link below to head back to our product page at americanmuscle.com if you're not there already. Speaking of install tips, since this is an axle-back you will need to do some small cutting as is the case with most 2015 axle-backs. Don't worry, it's really not a big deal at all as long as you take your time and follow the detailed instructions included with the particular exhaust. Either way, guys, if you do have any questions about the exhaust itself or about the actual install, feel free to reach out to a Mustang expert any time using our 1-800 number. They're always standing by ready to help out a fellow Mustang owner in need. Now it's time to hear how the Flowmaster Outlaw series axle-back sounds compared to our factory exhaust.

Super Aggressive Flowmaster Sound. Give your coyote powered S550 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 3" 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.

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 both fastback and convertible 2015-2017 GT Mustangs for both great looks and great sound.

Fitment: 2015 2016 2017 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: 3" Tip Size: 4.0"
Muffler Type: Straight-through Fitment: 2015-2017 GT
Will it fit my Mustang?
  • GT - 16, 15, 17

Fits both Fastback and Convertibles

People Who Bought This Item Also Bought

Most Helpful Reviews

5/5
Outlaw mufflers

Love it would definitely recommend them, they sound so good !!! Deep and throaty very 1960's sound

Helpful (9)

3/5
Very aggressive

Sounds really nice, but if you don't want to wear ear plugs or listen to the radio going down the highway than I wouldn't buy this system. The drone at 1900 rpm is ridiculous. Installation was easy and ...

Read More
Helpful (7)

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

Customer Photos (36) Submit Your Photo

View All 36 Photos

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22 Questions / 6 Answers

Ask a Question

Will this axle back fit with the ford performance x pipe with side exhaust on my 2015 mustang gt premium performance pack?

TheBear96

  • The Flowmaster Outlaw Series Axle-Back Exhaust will have no issues working with that setup.

    Rob D

Helpful (2)

Will this fit any resonator delete x pipe

Red

  • This Flowmaster Outlaw Series Axle-Back Exhaust would mount up to the stock exhaust locations, which most x-pipes would reuse.

    pserafi

Helpful (1)

Hello, I noticed a previous review stating that this Flowmaster had issues with being compatible with the GT Premium "convertible". The person writing the review said the muffler didn't fit and rattled when going over bumps. Is this accurate?

JasonH

  • These axles backs would work with both convertible and fastback models. You would not have any troubles with this exhaust on your car.

    Ricky36

Helpful (0)

Would installing this affect Manufacturer's Warranty on a 2017 GT Premium?

LarryP

  • Axles-backs should not affect the manufacturer's warranty no. However, each dealer does have their own taste in warranty and you would need to double check with the dealer offering your warranty.

    Ricky36

Helpful (0)

Do they have a black tip option? If no, can I paint the tips black ( it work well)?

JohnC

  • Unfortunately, there is not a Flowmaster Outlaw Series Axle-Back Exhaust with black tips. However, if you want to paint the tips we recommend having them anodized, or using high heat paint.

    VincentV

Helpful (0)

Anyone know if this will be a direct fit with the Corsa's double helix x-pipe?

GTPP16

  • The Flowmaster Outlaw Series Axle-Back Exhaust will fit with your x-pipe.

    Pat K

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 4.785311 4.8
  • Exhaust Note 4.858757 4.9
  • Fit & Finish 4.655367 4.7
  • Bang For Your Buck 4.819209 4.8



  • 5/5

    Installation Time: Shop Install

    Installation Cost: $100-$250

    December 11, 2015

    Outlaw mufflers

    Love it would definitely recommend them, they sound so good !!! Deep and throaty very 1960's sound

    Micah

    Year: 2015 Submodel: GT Chicago il

    Helpful (9)

  • 3/5

    July 13, 2016

    Very aggressive

    Sounds really nice, but if you don't want to wear ear plugs or listen to the radio going down the highway than I wouldn't buy this system. The drone at 1900 rpm is ridiculous. Installation was easy and only problem I had was one of the studs on the exhaust clamp snapped very easily while tightening.

    Huey

    Year: 2015 Submodel: GT

    Helpful (7)

  • 4/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    November 14, 2016

    Does the trick

    This should have been the stock exhaust Ford placed on the 2016 GT model. I love the cold start in my garage. It wakes half the neighborhood up in the morning lol

    Drese

    Year: 2016 Submodel: GT

    Helpful (6)

  • 5/5

    Installation Time: Less than 1 Hour

    March 13, 2015

    Great sound

    Only complaint was the black on one of the pipes is all scratched up. It takes 2 people once you get the pipes cut but all in all was fairly simple due to the fact this car has 146 miles on it.

    mcolli

    Year: 2015 Submodel: GT Mi

    Helpful (5)

  • 1/5

    Installation Time: Afternoon

    December 01, 2016

    2016 convertible mustang gt premium

    Doesn't clear the frame of the car and the convertible brace. Muffler rattles on frame and brace when hit small bumps and high rpms

    Ceejay

    Year: 2016 Submodel: GT

    Helpful (4)

  • 5/5

    Installation Time: Afternoon

    September 12, 2016

    Very aggressive, deep, muscle car sound!!!

    I bought the Flowmaster Outlaw Series Axel-Back exhaust with the full intention of making my 2016 GT sound like a muscle car is supposed to sound. Let me tell you, these did the job! Now, there is a catch. I bought them in conjunction with the Heartthrob H-pipes, so I cannot tell you how they sound with the factory exhaust, but if you like a deep, throaty, loud exhaust, this is the way to go. The H-pipes were a must, because it gets rid of most of the raspiness you would get with either the factory mid-pipes or x-pipes (I know this based on AM's article on mid-pipes and various sound clips). I just love this combo on my S550. Everywhere I go, I am breaking necks and receiving many compliments. You will not go wrong with this exhaust and h-pipe combo. *PLEASE NOTE* This combo is not a perfect bolt on kit. There is approximately 11 to 12 inches between the h-pipe and axle-back. You will either (A) need to have an exhaust shop bend some pipe to extend it, or (B) mark and cut the factory exhaust to have a seamlessly bent exhaust. I would personally go with (B), but I did not want to cut my factory exhaust, so I had to go with option (A). All in all, it took about 2-3 hours at my buddy's shop to do the install (my buddy did most of the work). Everything looks and sound incredible.

    Chris

    Year: 2016 Submodel: GT

    Helpful (4)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    April 27, 2016

    Just what i was looking for

    Best bang for the buck exhausts you can get here in AM, Makes you want to romp on it every time you get in gear to here that rumble, As well Practically zero drone on the highway.

    Chris

    Year: 2015 Submodel: GT

    Helpful (4)

  • 4/5

    Installation Time: Shop Install

    March 30, 2016

    Loud!

    Everything about these are awesome if you like loud...have the ford racing x pipe also. Sounds amazing. Only thing that sucked was followed the instructions to the point and the pipes as the went around the diff there was clearance concerns. As one side is about 1/4" away from the diff. But other than that it's great.

    Bdog

    Year: 2016 Submodel: GT

    Helpful (4)

  • 5/5

    Installation Time: Less than 1 Hour

    September 26, 2017

    Flow master outlaw

    Awesome sound ,awesome fit . Third set bought would use on my next as well .

    SteveP

    Year: 2017 Submodel: GT

    Helpful (3)

  • 1/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    September 17, 2017

    Drone Drone Drone

    Bought these a while back and also bought the scavenger x pipe sounded incredible at idle or giving it some gas in neutral. extremely loud while driving even at normal speeds for the streets at first I thought it was so cool seeing everyone's scared faces as I drove by but the drone got so annoying that I was getting headaches while driving to and from work. Rolling up the windows makes it worse as you get helicopter sound inside car. After two weeks I reinstalled my stock resonator which quieted it down significantly and sounded ok but not happy with it still. Recently bought the varex axleback for the s197 body style and custom fit to s550 and paired with my x pipe sounds so good with out the drone or being obnoxiously loud.

    Black550

    Year: 2016 Submodel: GT

    Helpful (3)

  • 5/5

    May 03, 2017

    Pitch perfect

    Arrived quickly, and in perfect condition. After researching ALOT of different axle back systems I landed on the outlaw. Great sound, exactly what I wanted. Those who don't want to hear in the car all the time, stay away.

    Chase

    Year: 2017 Submodel: GT

    Helpful (3)

  • 5/5

    Installation Time: Afternoon

    December 23, 2016

    Still love it

    I have had this on my car for 5 months now and still love the way it sounds every time I start her up. I paired this with a x-pipe and have heard nothing but complements at any of the car meets and while just driving down the road. Only complaints I have had so far are from my neighbors. I definitely recommend it to anyone that does not have to start there car at 11pm to go to work....

    3rdshift

    Year: 2015 Submodel: GT

    Helpful (3)

  • 5/5

    August 16, 2016

    Amazing sound!

    The installation is very simple when you have another person to help you. It has a definite noticeable sound difference at idle, more of a rumble. At higher RPM's (3500 ), pure heaven.. I kept the stock resonator to minimize the drone and avoid tickets. The only gripe I have is the price. Online, the price was $419.99.. In the magazine, it was $399.00.. I got boned for $20.00...

    Stymie

    Year: 2016 Submodel: GT

    Helpful (3)

  • 4/5

    Installation Time: Less than 1 Hour

    February 17, 2016

    NASCAR here i come! Use only with stock everything else!

    So, where do i start? After weeks, or months, of searching, I decided to pull the trigger and get these because of price and ease of install. Well let me just warn you guys that have a set up similar to mine. If you have neighbors, small animals, anyone or anything at all, within 100yds, they will not like you. Sounds like a Sprint cup car to be honest. I have BBK long tubes, cat-less mid pipes, the Heartthrob hpipe and this axle back. This is not tolerable inside the car at all, not even at idle. It sounds like a super loud race car, not a car to be driven on the street. Had this on for less than a day and I refuse to drive the car until I can afford something else. Be-warned, with stock everything else, it is amazing, but with all the rest, it sucks. Oh, and of course the black was scratched, and gouged in some places on the mufflers.

    Manhed

    Year: 2015 Submodel: GT Titusville, FL

    Helpful (3)

  • 5/5

    Installation Time: Shop Install

    February 02, 2016

    Been on a week now, and many compliments from strangers !

    Rec'd these about 2 wks ago and had a shop install them in about 2 hrs. Immediately loved them the moment I fired it up. Wife and I went for a Saturday afternoon drive to check em out. Paralleled parked in front of a boutique shop in a trendy suburb of Detroit. While putting change in the meter, the owner of the shop I parked in front of came up to me and said: "Now that's how a Mustang should sound." SOLD ! Worth every penny of the $399.99

    Stang15

    Year: 2015 Submodel: GT Metro Detroit

    Helpful (3)

  • 5/5

    Installation Time: Less than 1 Hour

    December 28, 2015

    Completely Satisfied!!!

    I ordered the Flowmaster Outlaw series exhaust because I wanted a more aggressive sounding GT. After the installation, let me tell you, I couldn't stop smiling!!! Now I have exactly what I needed! Thanks American Muscle for selling such a wonderful system. If you're looking for something better thank the factory system that doesn't hurt the wallet, this is it! And it arrived quickly!

    Noble

    Year: 2015 Nashville, TN

    Helpful (3)

  • 4/5

    Installation Time: Afternoon

    August 30, 2015

    Better than American Thunders in my opinion.

    Simple install. I was torn between the American Thunders and the Outlaws. I already had American Thunders on my last Mustang and they were nice, but I was looking for something a little louder with the Outlaws. I was worried that they wouldn't have a deep enough rumble but let me tell you, the 5.0 doesn't need the Thunders to have a rumble. It's throaty and aggressive and not overly loud so it's no obnoxious. Sounds great at low rpm's and higher rpm's. Mid range is decent.

    Seany

    Year: 2015 Submodel: GT New York

    Helpful (3)

  • 4/5

    Installation Time: Afternoon

    August 19, 2015

    Great exhaust for the money if you want it LOUD

    I was deciding between the Outlaw axle back and the Roush single tip axle back. After listening to them both (in person and online) I liked the loudness and aggressiveness of the Outlaws better. Obviously sounds are subjective, so check out videos on YouTube and make your own decision. But this is very loud! Its almost like straight pipes with a deep tone to them. If they are installed with the stock resonator, its not that bad, but still loud when you get on it. The stock exhaust is super easy to remove. It should take you around an hour on jack stands to get on the car. However, I installed them with an O/R H pipe. I used an angle grinder with a cutting wheel to chop the stock mufflers off, and the instructions were pretty clear to understand. Fitment was decent, but took me a while to get it right. If you don't have the patience, you might need to take it to a shop to get it perfect. Now the DRONE is something a lot of people are concerned about. To be honest, I haven't noticed much of a drone over other setups I've owned (Borla Stingers, LM1's, bassani). But on the highway running between 2K-2.2K rpm's, you might notice it a little if you're sensitive to it. Inside the cabin when driving you definitely hear it. I was worried my wife would not like it, but she was actually digging it. We can still talk fine, and i can even use sync to talk on the phone and the caller can hear me ok. They say after 500 miles or so it does quiet down a bit, but I haven't driven it that much yet. Or it could mean you're getting used to the sound. Either way its a great (and cheap) setup for the S550, and worth the money if you like loud, and don't want to spend over 500 bucks to make your car sound like a real car.

    Brandon

    Year: 2015 Submodel: GT Tampa, Fl

    Helpful (3)

  • 4/5

    Installation Time: Afternoon

    June 20, 2017

    Excellent Exhaust!

    Where do I begin with this exhaust? This is an amazing product! I love the low rumble it makes at idle, and when you lay on the gas, she screams! I think there's sort of a sweet spot between 2500k and 3500k where it just sounds awesome! I love going under a bridge and gunning it and hearing the Outlaws resonate in all their glory! The only reason I'm not giving this exhaust five stars is because of the DRONE, and this was definitely my biggest concern when I purchased this exhaust. It is definitely not a no drone system. It's got a decent amount of drone on the highway and you cannot accelerate without hearing it in the cabin. Initially I was disappointed by this, but now that I've had them on there for about a month and take them to road trips with the outlaws on, I have since gotten used to it, but it is important to note that there is a fair amount of drone in cabin noise. Other than that it's fantastic! That sounds amazing, fitment was perfect, and the chrome Flowmaster tips sticking out the rear looks mean! I don't think you'll find another exhaust that would beat this one for the price!

    JoshS

    Year: 2015 Submodel: GT

    Helpful (2)

  • 4/5

    Installation Time: Less than 1 Hour

    March 28, 2017

    2017 Mustang V6 MT

    Great product! Installation was pretty easy. Took about 45 minutes without a lift. I got these to go along with the GT exhaust I had put on my V6 Mustang, which is a direct bolt up to the factory exhaust. These mufflers have a very deep and aggressive tone but do have a decent amount of drone around 2200-2500 rpm depending on the load of the engine. Nonetheless, I would highly recommend these for someone wanting a muscular sound to accompany their V6 engine. Also, these aren't as loud as I thought they would be, given other reviews.

    TyE

    Year: 2017 Submodel: V6

    Helpful (2)

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