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2015-2022 Mustang 3.7L V6 and 2.3L Ecoboost ROUSH Exhaust Kit - Round Tip (304SS)

Part #: 421837

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Application: Mustang 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022
Installation Difficulty:
Intermediate ?
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Prices stated here are only for sales within the continental United States and ordered via the web site. Prices for other territories and countries may vary due to shipping fees, duties, and other factors.

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Product highlights for the 2015-2022 Mustang 3.7L V6 and 2.3L Ecoboost ROUSH Exhaust Kit - Round Tip (304SS):

  • Fits the 15, 16, 17, 18, 19, 20, 21, and 22 Mustang with both the V6 3.7L & I4 2.3L Ecoboost engines
  • ROUSH-designed high-flow mufflers with single inlets/outlets
  • More aggressive tone over stock
  • Made from corrosion-resistant high grade 304 stainless steel
  • Full mandrel-bent piping for consistent flow
  • 4" Flash-chromed dual wall tips embossed with the ROUSH logo
  • Uses OEM hangars and mounting points
  • Requires no welding
  • Some cutting required
  • Can be used with factory Ford rear valance
  • Same exhaust featured in the ROUSH Level 2 Performance Pack!
  • Includes all necessary hardware
  • ROUSH Limited Lifetime Warranty included

ROUSH’s Axle-Back Exhaust for the 2015-2022 I4 2.3L Ecoboost and V6 3.7L Mustangs is a great solution for anyone looking for a much more aggressive tone, and an overall better look!

Ford’s engine choices for the 15-22 Mustangs offers a variety of high-performing, yet affordable and economic, options to suite any budget or sensibility. This would include the V6 and I4 engines, which perform well beyond what their cylinder count would imply. However, Ford’s stock exhaust doesn’t quite have the aggressive tone or sound Mustang owners crave; this is where ROUSH Performance comes in!

ROUSH Performance has a specially engineered this exhaust that fits both the V6 3.7L and the I4 2.3L 2015-2022 Mustangs. Constructed from T-304 stainless steel, this exhaust is corrosion and stain resistant. Mandrel bends help to maintain high flow and reduce backpressure constantly throughout. This exhaust uses factory mounting points and will fit both V6 and I4 Mustangs without requiring any modification or welding. This exhaust system also greatly improves the sound and performance of your Mustang with single-tip high-flow chambered mufflers. To finish off the exhaust, ROUSH also includes 2 brand new round dual-wall exhaust tips, which are chrome flashed for superior corrosion resistance and are embossed with the ROUSH logo. Included will also be all necessary hardware to install this system. Instructions can also be found under the “Installation” tab on this product page.

Are you a 2015-2020 I4 2.3L Mustang owner who’s looking to get the most power and most aggressive sound ROUSH can offer? Take a look at our Level 2 Performance Pac, which includes this exhaust system!

WARNING: Cancer and Reproductive Harm -
Application Mustang 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022
Difficulty Intermediate
Time 1 hour 30 minutes
Tools Garage Tools
Instruction URL Download Instruction Manual