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Roush Quad Tip Active Axle-Back Exhaust (15-17 EcoBoost Premium)

Market Price $2,689.99 You Save 1% ($30.00)
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  • Item 389791
  • MPN# 421925

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Fastback Convertible
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Features & Details

  • ROUSH Active Axle-back Exhaust System
  • Select Between Touring, Sport, Track and Custom Exhaust Notes
  • Custom Programming with Included WiFi OBD2 Interface and Roush iOS App
  • Unique Open-Chambered Muffler Design
  • 304 Stainless Steel Construction
  • Full Mandrel-Bent Tubing
  • 4" Stainless Steel Quad Tips With Chrome Flashing
  • Cut & Clamp Installation
  • Fits 2015-2017 Premium Package EcoBoost Mustangs equipped with a Roush Rear Valance
ROUSH Active Exhaust System. Take total control of the performance and volume of your S550 EcoBoost Mustang with a ROUSH Active Exhaust system. Roush's proprietary Active Exhaust system ties directly into your Turbocharged Mustang's powertrain control module, opening and closing the mufflers valving based on throttle position.

Four Distinct Exhaust Sounds. The ROUSH Active Exhaust System includes a center console mounted selector knob that allows you to easily switch between four different sound modes on the fly. Choose from Touring, Sport, Track, and Custom.
  • Touring. The Touring mode closes the mufflers valves completely keeping the exhaust volume to an absolute minimum.
  • Sport. The Sport mode keeps the exhaust quiet during normal driving conditions. Accelerator position and vehicle speed are used to determine valve position, opening up under acceleration for a more aggressive sounding ride.
  • Track. The Track mode is wide-open. This mode keeps the exhaust tailpipe valves fully open at all times and doesn't restrict the raw sound of your Mustang. This mode is intended for track use and is not legal for street use.
  • Custom. The Custom mode lets you create a custom sound map with the included WiFi OBD2 interface and ROUSH iOS application to personalize the exhaust sound to your own tastes. With the app you gain full control over the position of the valves based on vehicle speed, rpm and accelerator position. Download the free ROUSH Active Exhaust App for iOS - Here

Quality Roush Construction. Constructed from fully mandrel-bent 304 stainless steel for a durability, corrosion resistance and long life, the Roush Axle-Back Exhaust features two unique open chambered mufflers with 304 stainless steel dual wall quad tips. The 4" quad tips are finished with a new chrome flashing process that is resistant to discoloration due to exhaust heat.

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

Application. This Roush Quad Tip Active Axle-Back Exhaust System is designed to fit fastback or convertible 2015-2017 EcoBoost Mustangs equipped with the factory Premium Chassis Package (Trim Levels: 200A/201A) and will require the use of the Roush Rear Valance 421894 or 421919 for proper installation (valance sold separately).

Download the Roush active exhaust app instructions - Here

Fitment: 2015 2016 2017 Details

What's in the Box
  • (1) Exhaust Pipe with Valve – LH
  • (1) Exhaust Pipe with Valve – RH
  • (1) Flashed Controller, Active Exhaust
  • (1) Vehicle Ready Wiring Harness 
  • (1) OBDII Active Exhaust Programmer
  • (1) Hardware Kit – Active Exhaust
  • (1) Switch, Mode Selector
  • (1) Switch Plate, Metal with Engraving
  • (1) Switch Bracket
  • (2) Bolt – M4 x 0.7 x 10
  • (2) Push Nut – 3/16” 
  • (3) Washer – M4 Nylon 
  • (7) Zip Tie with Edge Clip
  • (1) Knob, Knurled Style
  • (1) Set Screw – M3 x 0.5 x 6 
  • (1) J-Clip – M6  
  • (1) Bolt – M6 x 31 HEX
  • (2) Foam Tape 30 mm x 35 mm x 7.9 mm
  • (1) Micro Fuse – 10 AMP   
  • (20) Zip Tie – 7”  
  • (1) Multipurpose O-Ring, 5.6 mm
Installation Info
Tech Specs
Will it fit my Mustang?
  • EcoBoost - 16, 15, 17

Customer Photos

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3 Questions / 3 Answers

Ask a Question

Let me rephrase this I just want to know if the exhaust is 3" at the inlets


  • The Roush Quad Tip Active Axle-Back Exhaust has 2.5" diameter piping to the inlet of the muffler.


Helpful (1)

Could this fit a V6 S550?


  • This Roush Quad Tip Active Axle-Back Exhaust System is designed to fit the 2015-2017 EcoBoost Mustangs equipped with the factory Premium Chassis Package and will require the use of the Roush Rear Valance 421894 or 421919 for proper installation. This will not work in the V6 models due to the size of the exhaust and the need for the premium bumpers.


Helpful (0)

Is this a full 3" exhaust?


  • Hello! This is just an axle back exhaust, not a full exhaust. This replaces the pipe over the rear axle and mufflers at the back end of the car.

    Ryan H

Helpful (0)

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Customer Reviews (1) Write a Review

Overall Rating 5.0

out of 5 stars

Installation Time:Afternoon

  • Loudness / Volume 4 4
  • Exhaust Note 4 4
  • Fit & Finish 5 5
  • Bang For Your Buck 4 4

  • 5/5

    Installation Time: Afternoon

    May 16, 2017

    Awesome Exhaust

    Very nice product. Well worth the money, took about one afternoon to finish the install but gives the sound that all ecoboost owners want to hear.


    Year: 2017 Submodel: EcoBoost

    Helpful (2)

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