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Flowmaster American Thunder Classic Axle-Back Exhaust (11-12 Mustang GT, GT500)

Item 18413
AmericanMuscle no longer carries the Flowmaster American Thunder Classic Axle-Back Exhaust (11-12 Mustang GT, GT500). Please check out 1979-1993 Mustang Axle-Back Exhaust for an updated selection.
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    Video Review & Installation

    Hey everyone I’m Justin with and I’m taking a look at Flowmaster’s American thunder classic axle-back for your 2011 and newer Mustang GT. The American Thunder series axle-back is designed to give your Mustang that iconic Flowmaster sound, while giving you a little more horse power at the rear wheels. The system is constructed from durable 3 inch, 16 gauge aluminized tubing, and features 2 40 series chambered mufflers, everything is finished off with two 4 inch polished tips embossed with the classic Flowmaster logo. Now the installation itself should only take you about an hour using standard hand tools. Now lets see how Flowmasters American Thunder sounds compared to your factory exhaust.

    Product Information

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


    • Aggressive Flowmaster Classic 40 Series Sound
    • Polished Stainless Steel 4" Tips
    • Durable 409 Stainless Steel Construction
    • Includes Two Flowmaster Mufflers
    • Fits 2011-2012 GT and 2011-2012 Shelby GT500 Mustangs


    Classic Flowmaster Sound. Give your 2011-2012 Mustang GT or GT500 that unmistakeable Flowmaster sound with a nice power boost with the American Thunder Axle-Back exhaust system. This system improves exhaust flow using Flowmaster's patented chambered muffler design for that throaty, aggressive exhaust tone your high powered Pony deserves.

    Quality Construction. Constructed from durable 3" 409 stainless steel tubing for its resistance to corrosion, the Flowmaster axle back features two special 5" X 10" chambered Classic 40 Series Flowmaster mufflers with 4" diameter polished stainless steel tips for muscle car looks and sound. As an added bonus the tip is embossed with the "Flowmaster" logo for true custom styling.

    Application. This Flowmaster American Thunder Axle-Back exhaust system is designed to fit the 2011-2012 5.0 Mustang GT and 2011-2012 5.4L Shelby Mustang GT500 for both great looks and great sound.

    CA Residents: WARNING: Cancer and Reproductive Harm -

    Installation & What's in the Box

    Installation Info

    What's in the Box

    Hardware included:
    • (2) Mufflers
    • (2) 3/8" Hanger Keepers

    Tech Specs

    Axle-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
    Piping Size: 3" Tip Size: 4"
    Muffler Type: Chambered Fitment: 2011-2012 Mustang GT & 2011-2012 GT500

    Customer Reviews (156)

      Questions & Answers

      10 More Questions

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