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MP Concepts Quad Exhaust Rear Diffuser (15-17 GT Premium, EcoBoost Premium)

Market Price $329.99 You Save 29% ($95.00)
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$234.99 (each)

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  • Item 398118

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    Features & Details

    • Aggressive Race Inspired Styling
    • Durable Injection Molded ABS Material
    • Features a Stippled Grained Texture
    • Straight Forward Installation - Cutting Required
    • Backup Sensor Compatible
    • Intended for use with Aftermarket Quad Exhaust Systems
    • Designed for Premium Chassis Packages Only (Trim Levels: 200A/201A/400A/401A)
    • Fits 2015-2017 GT Premium and EcoBoost Premium Mustang Models
    Race Inspired Styling. Add an aggressive race car inspired appearance to your 2015-2017 Premium Package Mustang by installing a MP Concepts Quad Exhaust Rear Diffuser. Designed for use with aftermarket quad exhaust systems, this Diffuser nicely compliments the lines of your Premium Package equipped Mustangs rear bumper cover.

    Quality Construction. MP Concepts manufactures their Quad Exhaust Rear Diffuser from injection molded acrylonitrile butadiene styrene (ABS) plastic using the original OEM CAD data from Ford to ensure a perfect fit. ABS 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. 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 MP Concepts Rear Diffuser is simple and straight forward. 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. Reuses factory reflectors.

    Backup Sensor Compatible. This MP Concepts Rear Diffuser can be installed on Mustangs equipped with or without factory installed back-up sensors and will not affect sensor operation.

    Application. This MP Concepts Quad Exhaust Rear Diffuser is specifically designed to fit 2015-2017 GT and EcoBoost Mustangs equipped with the factory Premium Chassis Packages only (Trim Levels: 200A/201A/400A/401A). Intended for use with aftermarket quad exhaust systems.

    Please Read. If you are having trouble determining what style bumper your Mustang is equipped with please refer to the comparison image above.

    Fitment: 2015 2016 2017 Details

    MPN# 398118

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (1) Diffuser - Center Section
    • (1) Diffuser - Left Side
    • (1) Diffuser - Right Side
    • (4) Spacers
    Installation Info
    Will it fit my Mustang?

      Customer Photos (7) Submit Your Photo

      View All 7 Photos

        Questions & Answers (12)

        5 Top Rated Questions

        Would this diffuser work with the Corsa Quad Tips? Also, could we have more product pictures with a view on the exterior of the diffuser (as if we were looking at it while it was attached to the s550s bumper. Can't really tell what it will look like when attached to a stang with the stock pictures provided, seeing as they're shots of the interior of the diffuser)

        • This is indeed intended for use with Aftermarket Quad Exhaust Systems. We are constantly looking at expanding our productpictures and will submit this request for additional pictures. 

        Helpful (2)

        Will I have to remove the entire bumper like I would in the roush? Also will this fit the stock premium valance or will I have to get a quad valance?

        • The rear bumper will not need to be removed in order to install this diffuser.

        Helpful (1)

        Will I still be able to use my MMD rear custom fit splash guards with this diffuser? Thanks.

        • The MMD splash guards will still work yes.

        Helpful (0)

        When will a review and installation video be out for this diffuser am?

        would this work with the oem 2018 mufflers and exhaust tips?

        • This will not work on a 2018 Mustang. It is designed for Premium Chassis Packages Only (Trim Levels: 200A/201A/400A/401A) on a 2015-2017 Mustang.

        Helpful (0)
        Post Your Question
        7 More Questions
        Has anyone bought the diffuser and installed the Corsa quad tips with no problem? 0 answer
        Hello, it's hard to tell from the pictures but is this a one piece diffuser? Meaning is the diffuser a continuous piece from side to side? Or is it a 3 piece like the roush one? Thank you. 1 answer
        Some seems to have problem fiting this diffuser with the 4 tipped Corsa. Could you confirm that this diffuser will work with the 4 tipped Corsa touring axleback and the tips would be centered in the opening, without modifing the exhaust? 1 answer
        Would this diffuser allow me to use an '18 GT quad tip exhaust on my '17 GT? Preferably the Borla S-Type quad tip. 1 answer
        Would this product work with the Ford Performance extreme quad tip cat back part # M-5200-M8EBA? 1 answer
        Can you confirm that this diffuser will work with the quad tipped Corsa Xtreme catback ( and the tips would be centered in the opening? 0 answer
        Will this work with the Roush axle-back quad exhaust? 1 answer

          Customer Reviews (9) Write a Review

          Overall Rating 3.9

          out of 5 stars

          Installation Time:Less than 1 Hour

          • Fit 3.444444 3.4
          • Appearance 4.555555 4.6
          • Bang For Your Buck 4.111111 4.1

          • 4/5

            May 13, 2019

            Super cool look

            Look is awesome no denying but the hard ware that is supposed to transfer from OEM to mp concept valence doesn't fit and I used different hardware.


            Year: 2016 Submodel: GT

            Helpful (0)

          • 3/5

            Installation Time: Less than 1 Hour

            April 26, 2019

            Not bad, but not great.

            I’d give this piece a 3/5. For the most part it looks good, but the seams on the sides are absolutely awful the snap on pieces don’t snap on very well and the edges are rough. The rest of it looks nice, though. The 18 quad tipped axle backs should line right up with it.


            Year: 2016 Submodel: GT

            Helpful (0)

          • 3/5

            Installation Time: Afternoon

            April 15, 2019

            Not a great fit

            Overall its pretty easy to take off the old diffuser, cut off the rest of the plastic. The reverse light is held in place by the factory hardware and some spacers. They do not actually thread into the valence itself. Doesnt leave me confident in feeling that it is secure. Wouldn’t recommend this based off of fitment. The side extension tab on one side was already broken off as well as niether side “snapping into place easily.” The tabs bend easy and dont want to snap in. The end fitment looks alright but just knownwhat youre getting into.


            Year: 2016 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            February 23, 2019

            Looks very nice

            Makes a big difference and looks OEM too. I love it.


            Year: 2015 Submodel: GT

            Helpful (1)

          • 4/5

            Installation Time: Afternoon

            February 09, 2019

            Solid Product BUT Patience Required

            This rear diffuser is NOT EASY TO INSTALL. Some steps in the instructions are not as clear or as easy to complete as they seem. The bumper does NOT need to come off but I recommend putting your car on jack stands to prop up the rear so you can work underneath. The ends come separated from the main piece of the diffuser which creates a minor gap in the back corners. You will also have to cut off part of the stock diffuser and reconnect the reverse light. It looks great it's finally finished.


            Year: 2017 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            January 22, 2019

            Great product

            Looks pretty awesome just lne side was hard to fit in.


            Year: 2016 Submodel: GT

            Helpful (1)

          • 5/5

            November 14, 2018

            Great fit

            Looks great, easy install and you keep the OEM reverse parking sensors in place. Thanks MP Concepts!


            Year: 2016 Submodel: GT

            Helpful (8)

          • 1/5

            Installation Time: Less than 1 Hour

            September 21, 2018

            It does not fit

            It says above that it will work with Corsa quad. It will not. fitment is off. Also the push pins where it connects on the sides the way it was created is not correct either. the holes are 90 degrees off. the side pieces for the side trims of the diffuser are very flimsy and connect with sliding them together. They cannot support the trim.


            Year: 2017 Submodel: GT

            Helpful (15)

          • 5/5

            Installation Time: Less than 1 Hour

            September 18, 2018

            amazing product

            the rear diffuser will look good on your mustang GT or Ecoboost for a better performance quad exhaust!!!


            Year: 2018 Submodel: EcoBoost

            Helpful (6)