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RTR Rear Diffuser (18-20 GT; 19-20 EcoBoost w/ Active Exhaust)

Item 403279
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Market Price $349.99 You Save 14% ($50.00)
Our Price

$299.99 (pair)

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    Features & Details

    • RTR Aggressive Track Inspired Styling
    • Durable Injection Molded TPO Material
    • Features a Grained Texture
    • Straight Forward Installation - Cutting is Required
    • Sold as a Pair; Driver and Passenger Side Included
    • Fits 2018-2020 GT Mustang and EcoBoost Models with Dual Quad Exhaust
    Modern Aggressive RTR Styling. Add an aggressive track inspired appearance to your GT Mustang with the same exact Rear Diffuser that is featured as original equipment on the 2018-2020 Mustang RTR. Designed and developed in conjunction with Vaughn Gittin Jr., this RTR Diffuser was designed to offer a tastefully more pronounced Rear diffuser for those who want a bit more in comparison to the subtle factory rear diffuser.

    High Quality TPO Construction. RTR manufactures their Rear Diffuser from an injection molded thermal plastic olefin (TPO) material 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 driving. This Rear Diffuser is completed in a fine grained stippled texture for a factory look that helps to hide the appearance of rock and stone impacts.

    Straight Forward Installation. Installation of the RTR Rear Diffuser is simple and straight forward. The Diffuser installs easily with a combination of hardware and 3M automotive bonding tape. However, it will require permanent modification to the stock rear bumper cover to remove a section of the factory diffuser. Installation can be completed in about two hours.

    Application. This RTR Rear Diffuser is designed to fit 2018-2020 Ford GT Mustang and EcoBoost models equipped with dual quad exhaust tips only. Driver and passenger side Diffusers are included.


    Fitment: 2018 2019 2020 Details

    MPN# 403279

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (1) Driver / Left Side Rear Diffuser
    • (1) Passenger / Right Side Rear Diffuser
    • (2) Diffuser Brackets
    • (4) 5mm x 10mm Short Screws
    • (2) 5mm x 20mm Long Screws
    • (4) 5mm Washers
    • (1) Adhesion Promoter
    Installation Info
    Will it fit my Mustang?

      Customer Photos (6) Submit Your Photo

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        Questions & Answers (4)

        4 Top Rated Questions

        Will the Roush valence aero foil kit fit perfectly with this diffuser design?

        • Unfortunately, the Roush rear valance aero foil kit will not fit properly with this RTR rear diffuser product due to this part interfering with the install of the Roush kit.

        Helpful (1)

        Could this item work for my 2019 mustang GT with out active exhaust

        Is there actual cutting involved like the 15-17 rear diffuser from RTR? Based on the pics it looks like it slips over the stock ones and is held by double sided tape.

        • This RTR Rear Diffuser is only compatible with 2018-19 models.

        Helpful (0)

        why won't this fit a 2018 eco boost with a quad exhaust?

        • This diffuser is designed for the 18-19 Mustang GT models.

        Helpful (0)
        Post Your Question

          Customer Reviews (3) Write a Review

          Overall Rating 5

          out of 5 stars

          Installation Time:Less than 1 Hour

          • Fit 4.333333 4.3
          • Appearance 5 5
          • Bang For Your Buck 3.666667 3.7

          • 5/5

            Installation Time: Afternoon

            May 02, 2019

            RTR Rear Diffuser

            Aside from cutting, install is a breeze. Just wish they would have told you about your reverse light wiring being right behind one of the fins. I ended cutting completely through that and having to solder them back together. Love the look!


            Year: 2018 Submodel: GT

            Helpful (1)

          • 5/5

            Installation Time: Less than 1 Hour

            October 19, 2018

            More aggressive rear

            Rear end looks a lot stronger with these installed. Install was very simple using a new sharp razor blade knife to cut out diffusers instead of using a electric cutting tool


            Year: 2018 Submodel: GT

            Helpful (12)

          • 5/5

            Installation Time: Less than 1 Hour

            September 03, 2018

            Amazing product

            The diffuser just went in perfect and I did not have any problems putting it on, and it looks amazing.


            Year: 2018 Submodel: GT

            Helpful (13)

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