Free Shipping On Orders Over $49. Details

Talk to a Mustang Enthusiast
M-F 8:30A-11P, Sat-Sun 8:30A-9P
Win $15,000!! Enter Now
Coronavirus: We are Open For Business, Prioritizing health and safety Learn More

Roush Axle-Back Exhaust (15-17 GT)

Item 387039
Call a Mustang Enthusiast at 1-877-887-1105
M-F 8:30A-11P, Sat-Sun 8:30A-9P
Market Price $673.99 You Save 12% ($78.00)
Our Price


FREE Shipping

Will this fit your Vehicle?

Select a different vehicle Help?
Update or Change Vehicle
In Stock

Ship to: Ashburn - 20149
Sorry, please enter a valid US or CA postal code
We're sorry, zip can't be updated at this time.
    Create a list
    Add to New List

    Saved - View your saved items

    We're sorry. We couldn't save this product at this time.

      Review & Installation Video

      What's up everybody? Justin with Welcome to my quick breakdown of the Roush axle-back exhaust system available for your 2015 Coyote powered GT. As you guys all just heard, the 2015 Roush axle-back definitely lives up to the claim of being one of the more aggressive axle-back systems available for your new GT. The same was true with the '11 to '14 S197 axle-back, and that same super aggressive tone has definitely found its way over to the new S550 kit.That super angry or aggressive tone does come courtesy of Roush's unique open chambered or hollow chambered mufflers as they call them. These things are unique in the fact that they don't use a traditional fiberglass packing material. This allows for that really aggressive tone you guys heard earlier. At the same time, it's going to keep any interior noise or drone to an absolute minimum. In addition, these mufflers are a straight through design, meaning any performance you might see, while minimal typically here with an axle-back, will definitely be a little bit more than what you might see with a traditional chambered muffler.All right, guys, going over the build quality a little bit here. You will notice what little piping there is has all been mandrel-bent two and a half inches in diameter. The entire system has been constructed from quality 304 grade stainless steel. This does include the four inch slash cut tips. These tips are cool because they do feature Roush's unique new chrome flashing process which they say will help reduce any discoloration over the years.By now, guys, you should know that with any 2015 axle-back install there is some cutting required. However, like I tell you in some previous videos, as long as you take your time and follow some basic guidelines you should be good to go. These guidelines do include making sure you have a nice fresh Sawzall blade on hand, make sure you wear your eye protection of course, and last but not least measure twice and cut once. Thankfully, Roush does include some really nice detailed instructions with this kit on where to cut. As long as you take your time, follow the instructions, you can expect to spend about two hours from start to finish getting this thing bolted up.If you guys are looking for one of the most aggressive axle-back systems from one of the most recognizable names in the Mustang world then be sure to check out the Roush axle-back for your Coyote powered GT right here at

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Aggressive Exhaust Sound
      • Unique Open-Chambered Muffler Design
      • 304 Stainless Steel Construction
      • Full Mandrel-Bent Tubing
      • 4" Round Stainless Steel Tips w/ Chrome Flashing
      • Fits All 2015-2017 GT Mustangs


      Aggressive Muscle Car Sound. Let your 5.0L Coyote engine howl with a Roush Axle-Back Exhaust. This innovative new Roush exhaust system features a hollow chambered muffler that results in increased air flow and a unique sound, with no in-cabin "boom" normally found with performance exhaust at cruising speeds.

      Quality Roush Construction. Constructed from mandrel bent 304 stainless steel for a durable long life, the Roush axle-back exhaust system features two unique open chambered mufflers with 304 stainless steel 4" tips. The 4" tips are finished with a brand new chrome flashing process that is resistant to discoloration due to exhaust heat.

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

      Application. This Roush Performance Axle-Back Exhaust System is designed to fit the all 2015-2017 GT Mustangs, including Fastback and Convertible models, for both great looks and great sound.

      Fitment: 2015 2016 2017 Details

      MPN# 421834

      CA Residents: WARNING: Cancer and Reproductive Harm -


      Customer Reviews (100+)

      Write a Review

      Ratings Summary

      4.9 out of 5 overall rating from 100+ customers

      Installation Time: Afternoon

      Installation Cost: $100-$250

      • March 08, 2020

        5 2015 GT - Anonymous Installation Time: Less than 1 Hour

        Mustang GT Roush axle-back

        Love the way my car sounds. The install is super easy. If you have a way to lift your car, you can do it yourself

        Helpful (0)
      • February 28, 2020

        4 2016 GT - KennethS Installation Time: Less than 1 Hour

        Pricey but sounds awesome!

        This thing fit perfectly on the hanger and lined up nicely with the exhaust cutout. I turned the tips slightly to better line up with the cutouts. Perfect sound!

        Helpful (0)
      • February 25, 2020

        5 2015 GT - MarkH Installation Time: Less than 1 Hour


        Paired these with the pypes H pipe resonator delete. Sounds awesome, pretty darn loud but not unbearable loud. Definitely recommend you go with a H pipe over the X when going with roush. Keeps from being so raspy. Also install was super spot on, took about 30 min to get bolted up.

        Helpful (0)
      • February 24, 2020

        5 2017 GT - TroyGodwin Installation Time: Shop Install Installation Cost: $100-$250

        Roush Exhaust Review

        Looks and sounds awesome however, I didn't notice much of a difference until I removed the resonator so plan on budgeting for that as well. The Roush exhaust has a nice deep rumble until you get on it then it sounds like you went into beast mode. I get compliment’s all the time on how nice my car looks and sounds at car shows. I’m extremely happy with my decision to go with an aggressive exhaust system.

        Helpful (0)
      • February 15, 2020

        5 2015 GT - DavidBurrow Installation Time: Less than 1 Hour

        Fantastic product

        I ordered the Roush axle back for my 2015 GT and could not be more pleased. The installation was a breeze and the absolutely sound great. I totally recommend them.

        Helpful (0)
      • February 04, 2020

        5 2017 GT - Raidersfan64 Installation Time: Less than 1 Hour

        I love the sound

        Better than before. Sounds aggressive for Cali standards with all dem laws

        Helpful (1)
      • January 22, 2020

        5 2015 GT - staps065 Installation Time: Less than 1 Hour

        Great enhancement to my stock GT

        I bought my stock GT Premium used and it still had the factory exhaust. I was surprised by how quiet it was and it didn't have the Mustang growl I'm used to. Well, I've upgraded the exhaust on every GT I've owned and had Roush axle-backs on my 2012. I LOVE the new sound and roar of these pipes. I have a convertible so I didn't want it too loud but wanted that signature sound. The Roush axle-back mufflers did the trick. Love them!

        Helpful (0)
      • January 01, 2020

        1 2017 GT - RWS28


        Ordered the Axle back for my 2017 GT REALLY disappointed when I opened the box and there was quad tips inside which can only be used with a 350 diffuser. Been waiting 3 days to hear if they will send me correct parts. Spend this kind of money and shouldn’t have to wait for clarification.

        Helpful (2)
      • November 16, 2019

        5 2015 GT - KimH7609 Installation Time: Less than 1 Hour

        Roush axle back

        I love it! Car sounds as good as it looks now!!!!!!!!!!!!!!!!!

        Helpful (1)
      • October 14, 2019

        5 2016 GT - Toufic Installation Time: Less than 1 Hour

        It sounds like a mustang should ! I love it best bang for your buck!

        Helpful (0)

      Questions & Answers (59 answers)

      5 Top Rated Questions

      Bought a 2017 GT Fastback in December (2017) Will installing these or any aftermarket axle-back mufflers affect my five year warranty from Ford?

      • We suggest reaching out to the dealership to see if the Roush Axle-Back Exhaust will affect the warranty.

      Helpful (12)

      I have an 11 month old son, will this be too loud for him in the back seat? I also have a 2006 with a bunch of work done to it and it is too loud for him to ride in so when my wife and I go to shows I need this to be noticeable louder but yet not too loud for my son. Thanks.

      • Hello! Unfortunately loudness is totally subjective to each person, as far as exhaust systems go, an axleback is the more quiet option. However, Roush is one of the louder axleback exhaust systems. I would recommend trying to find someone local with an axleback setup on their mustang, so you can hear it in person to decide.

      Helpful (6)

      will this fit 2015 GT convertible?

      • This will fit with the 2015 GT convertibles.

      Helpful (6)

      I will have this set for my mustang gt 10/12/17,my question is what is in the inside of these mufflers.

      • The mufflers in the Roush Axle-Back Exhaust will contain Roush's proprietary sound deadening materials to enhance the exhaust note of your Mustang.

      Helpful (5)

      Are these Roush axle back exhaust legal in the state of California?

      • We recommend that you check with your local ordinances to determine if their are any decibel limits, but in terms of emissions you'll have no issues. When it comes to the exhaust, if it's not catalytic converters or headers, you won't have to worry about emissions.

      Helpful (4)
      10 More Questions
      Will this exhaust pair nicely with the Mishimoto H-pipe? I see all of the pairings going with an X pipe, but I really want that low pitched muscle rumble. 1 answer
      I have 2 3 years warranty for my Mustang GT. Is there any warranty issue if I would modify the original exhaust system? 1 answer
      Hi I have a 16' GT Convertible. I love my car, but I want some more sound. I am looking for the deep rumbling sound, not the screaming one. Will Roush Axle-Back Exhaust be the right way to go? As of now, I don't want to spend to much money, just want some more sound. Down the road I am also thinking of getting a Roush Supercharger. (727 hp) Will this setup still be okay if I am getting the Supercharger? Does black tips exist for this ? 1 answer
      will this muffle system void the ford warranty 1 answer
      Any drone heard with this Axle-Back and an X-Pipe? 1 answer
      Does anybody have any suggestions of which x pipe to pair with this axle back? 2 answers
      Will this pair up nice with my Corsa Helix 3 1/4 inch X Pipes? I don’t wanna lose the corsa rumble to roushs rasp. If not what would go well with corsa x pipes other than corsas own axlebacks? 0 answer
      Will this work with a 3in x pipe? 0 answer
      I know the outlet diameter of the tips is 4.5", but what is the diameter of the inlet (where the tips attach to the muffler)? 1 answer
      Did you measure your product for 95db max at 3000rpm 25 inches away at a 45 degree angle yet? If not I need to order from another manufacturer. New California law. If you comply I’ll buy your product. 1 answer

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Muffler assembly - Driver Side
      • (1) Muffler assembly - Passenger Side
      • (2) Tips
      • (4) Clamps

      Tech Specs

      Cat-Back Exhaust Specifications
      Piping Material:304 Stainless Steel Tip Material :304 Stainless Steel with Chrome Flashing
      Piping Size:-"Tip Size:4"
      Muffler Type:Open chamberedFitment:2015-2017 GT

      Will It Fit My Mustang

          Related Mustang Categories