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Flowmaster American Thunder Dual Exhaust System; Side/Rear Exit (11-18 6.2L Sierra 1500)

Item S501881
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Market Price $990.09 You Save 13% ($129.14)
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      Product Information

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


      • Split Rear Side Exit Exhaust
      • Cat-Back System with Moderate Sound Level
      • Dyno-Tuned for Maximum Performance
      • 2.5" 409S Stainless Steel Construction
      • 3.5" Round 304 Stainless Polished Tips
      • 50 Series HD Muffler w/ Welded Baffle
      • Made in the USA
      • Bolt On Design, Some Cutting May Be Required
      • Fits 2011 to 2018 GMC Sierra 6.2L Extended/Double Cab and Crew Cab Models


      The Right Growl for Your Truck. Most truck owners install cat-back exhaust systems to improve their vehicle’s performance. However, some of them have the side effect of creating loud roars that aren't great for daily driving on city roads. That’s where the Flowmaster American Thunder Stainless Steel Cat-Back Exhaust comes in. By only producing a moderate sound from the 50 Series HD muffler, this exhaust hits the right note of aggression, without becoming obnoxious.

      Built to Last. This 2.5" mandrel-bent 409S Stainless Steel Exhaust System boasts of the patented Flowmaster Delta Flow Muffler technology, allowing you to reach peak performance with a moderate sound. Complete with dual 3.5” round 304 stainless steel tips, this American Thunder Cat-Back features a split rear side exit design.

      Made by the Experts. For over thirty years, Flowmaster has been creating the top mufflers in the country. In fact, they pioneered some of the top innovations in the industry, registering numerous patents in the process. So when it comes to exhaust systems, it's a no-brainer. Flowmaster is the way to go.

      Bolt On Installation. Flowmaster engineered their American Thunder Cat-Back to be a direct upgrade replacement of the factory Sierra exhaust system. All of the necessary hardware is included and installs easily with basic hand tools. Depending on your cab and box configuration, some cutting to the exhaust piping may be required.

      Application. The Flowmaster American Thunder Stainless Steel Split Rear/Side Exit Cat-Back Exhaust is designed to be used on the 2011-2018 6.2L GMC Sierra's with the following cab and box configurations.
      • Extended Cab with the Standard Box
      • Extended Cab with the Short Box
      • Double Cab with the Standard Box
      • Crew Cab with the Short Box
      • Crew Cab with the Standard Box

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      Fitment: 2011 2012 2013 2014 2015 2016 2017 2018 Details

      Flowmaster 817602

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Inlet Pipe
      • (1) 6.5’ Bed Extension
      • (1) Muffler
      • (3) Tailpipes
      • (2) Side Exit Pipes R/L
      • (2) Rear Exit Pipes R/L
      • (2) 3.5” Round Tips
      • Installation Hardware

      Tech Specs


      Customer Reviews (100+)

        Questions & Answers

        10 More Questions

        Will It Fit My Sierra 1500

        • 6.2L V8 - 11, 12, 13, 14, 15, 16, 17, 18

        Designed for Extended/Double Cab and Crew Cab Models Only

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