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Authority Motorsport R550 Rear Diffuser (18-23 Mustang GT)

Item 432565
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Our Price

$295.00 (each)

FREE Shipping + $25.00 Oversized Item Fee Market Price $339.25 You Save 13% ($44.25)

Open Box from $177.00

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      Product Information

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


      • Rear Diffuser
      • Reduced Drag
      • Increased Downforce
      • Improved Handling and Acceleration
      • Limited Lifetime Warranty
      • Fits 2018-2023 Mustang GT Models


      Performance. The Authority Motorsport R550 Rear Diffuser will take your Mustang GT to a whole new level of performance. This rear diffuser increases downforce, lowers drag, enhances handling, and accelerates more quickly than ever before, giving you the most thrilling driving experience ever.

      Durable. High-quality ABS plastic is used to manufacture the R550 Rear Diffuser in the USA, assuring its sturdiness and longevity. Your Mustang GT will stand out from the competition because of its classy matte black design.

      Installation. Putting this Authority Motorsport R550 Rear Diffuser on your Mustang GT is easy and requires no drilling.

      Warranty There is a limited lifetime warranty on this product.

      Application. The Authority Motorsport R550 Rear Diffuser fits 2018-2023 Mustang GT models.



      Authority Motorsport 912138000961

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Rear Diffuser
      • Hardware
      • Instruction Manual

      Customer Reviews (2)

        Brand Image

        Reviews of Authority Motorsport Exterior products have an average rating of 4.8 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • GT - 18, 19, 20, 21, 22, 23