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Roush Rear Valance Aero Foil Kit (18-20 GT; 19-20 EcoBoost w/ Active Exhaust)

Item 404870
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Market Price $146.00 You Save 4% ($6.01)
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$139.99 (pair)

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      Review & Installation Video

      Product Information

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


      • Aggressive Track Inspired Styling
      • Increases Rear Downforce
      • Injection Molded TPO Construction
      • Black Stipple OEM Style Finish
      • Simple Installation - Minor Drilling Required
      • Fits 2018-2020 GT Mustang and 2019-2020 EcoBoost Mustangs with Active Exhaust


      Track Inspired Styling. Add aggressive track inspired styling to your 2018-2020 GT Mustang by installing a Roush Rear Valance Aero Foil Kit. This Rear Valance Aero Foil attaches to your GT's rear diffuser to considerably alter the overall appearance of your Mustang's rear end. This Roush Rear Valance Aero Foil Kit is a great way to set your 2018-2020 GT Mustang apart from all the rest.

      Functional. Roush designed their Rear Valance Aero Foil Kit employing techniques used in professional racing. This Rear Valance Aero Foil will improve your 2018-2020 Mustang's aerodynamics by separating airflow beneath the car, allowing a smaller portion to follow the under-body contours, increasing rear downforce.

      Roush Quality. Roush manufactures their Rear Valance Aero Foil Kit in the USA at their own plastics manufacturing facility from OEM quality high pressure injection molded high-strength thermal plastic olefin (TPO) using the original OEM CAD data from Ford to ensure a perfect fit. TPO is an extremely strong material known for its light-weight, superior durability and impact resistance - making it perfect to withstand the hazards of daily driven vehicles. The Grille is then completed in a black, stipple textured finish for aggressive good looks.

      Simple Install - Drilling Required. Roush designed their Roush Rear Valance to install utilizing both double sided automotive tape and mechanical fasteners, so drilling will be required for installation. Roush provides the required mounting hardware and installation instructions. Installation should take about an hour to complete.

      Recommended Upgrade. Complete your 2018-2020 Mustang's aggressive track inspired appearance by installing Roush's High-Flow Lower Grille Opening Kit (part# 422081) and 3-Piece Aero Chin Spoiler (part# 422082) - sold separately.

      Application. This Roush Rear Valance Aero Foil Kit is designed to fit 2018-2020 GT Mustang and 2019-2020 EcoBoost Models with the Active Exhaust only. Does not fit V6 or Shelby GT350.

      Fitment: 2018 2019 2020

      Roush 422085

      CA Residents: WARNING: Cancer and Reproductive Harm -


      Customer Reviews (32)

      Write a Review

      Ratings Summary

      4.8 out of 5 overall rating from 32 customers

      • May 21, 2020

        5 2019 GT - eagleman

        roush rear valance love it

        makes the rear end kinda looks a lambo kinda the mufflers looks great and makes the car look a little bit lower amd mean looking

        Helpful (0)
      • May 09, 2020

        5 2020 GT - JoseG

        Great look

        This gives your rear a mean look! Looks great! Easily install

        Helpful (0)
      • April 16, 2020

        5 2019 GT - Paul

        Looks Aggresive!

        Easy install. Improves the aggressiveness of the rear bumper.

        Helpful (3)
      • January 31, 2020

        5 2019 GT - MadMaxMustang

        Rear valance

        Very easy easy to install! I watched the video for it and was very helpful! Only took about 30 minutes! Looks great! I have gotten a lot of compliments already! I would recommend it to anyone who wants something that not many even think about!

        Helpful (4)
      • January 15, 2020

        5 2018 GT - Aubut


        Sell $64.00 cdn on Ebay Canada.Included tranportation.

        Helpful (4)
      • January 13, 2020

        5 2019 GT - Anonymous

        White lightning's new parts

        Great product from Roush,easy installation makes my Pack 1 automatic look great, many more parts on order, thank you American Muscle , great parts , great price , great site

        Helpful (3)
      • October 30, 2019

        4 2019 GT - TWHITE

        Roush Rear Valance Aero Foil Kit

        Easy to install and made the car POP. Good quality but still pricey for what you get

        Helpful (3)
      • October 10, 2019

        5 2018 GT - BrandonButch

        The aggressive look I needed!

        I knew I needed something to make my GT look more aggressive from the back, but I didn't know what would really make it pop like I envisioned. So I ordered this Roush valence and man, this is exactly what I had in mind! It adds a very aggressive, mean look to the back end of your Mustang! Definitely recommend adding a spoiler as well if you want to complete the aggressive look. Install was very simple, took about 30 minutes in the driveway. Looks OEM. Very satisfied!

        Helpful (4)
      • October 07, 2019

        5 2019 GT - MiltonR

        Roush rear aero foil

        Very easy to install dresses up the rear end just Jack up one side of the car and everything can be done with no problems recommended for 2019 mustang gt 5.0 owners

        Helpful (3)
      • September 23, 2019

        5 2019 GT - Browningbuck

        Adds a nice twist to the back end

        fit is perfect and is a very noticeable line change

        Helpful (3)

      Questions & Answers (11 answers)

      5 Top Rated Questions

      Do you have list exact tools (sizes) that will be needed to install?

      Will this fit with the RTR rear valence?

      Will this fit a 2019 GT Premium Performance pack without active exhaust?

      • This will only work with the active exhaust feature.

      Helpful (0)

      I have a 2018 gt with out active exhaust will this fit?

      • This will only work with the Mustangs that have the active exhaust feature.

      Helpful (0)

      Is there a reason why this wouldn’t fit the 2018-20 base EcoBoost other than the fact that the base has dual tips instead of quad tips like the premium? Thanks!

      Post Your Question
      6 More Questions
      Will this install if I already have the MMD Rear Diffuser Fins in place? Item 406534-NL 1 answer
      Will this fit on a 2019 mustang EcoBoost non performance pack but with active exhaust? 0 answer
      Will these fit the Roush rear valance for 2015-17 GTs? 1 answer
      Will this piece fit a 2016 PP rear diffuser? 1 answer
      will this fit a 2018 eco boost with performance pack 1 answer
      Will this be an exact fit with the rtr diffusers for a more aggressive look? 1 answer

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Driver Side Rear Diffuser
      • (1) Passenger Side Rear Diffuser
      • (2) Brackets
      • (6) Self-Tapping Screws
      • (4) Bolts
      • Double-Sided Tape
      • Instructions

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