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    Flowmaster Exhaust Systems - 817669

    Cat Back Exhaust - American Thunder Series
    Showing 1 - 7 of of 22
    • $255.97 - $1,999.97
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    • Style:
      Dual rear/dual side exit (409 Stainless)
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    Flowmaster Exhaust Systems Part #817669 Customer Reviews

    Average Rating

    24 Customer Reviews

    Great sound

    Reviewed by George B (WEST CHESTER, PA) Reviewed for a 2017 Chevy Silverado — Dec 08, 2017 2:02 AM

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    I installed the flowmaster American thunder exhaust on my 2017 Silverado all went well, my truck sounds great and i did notice an increase in my gas mileage. The exhaust was easy to install, I opted for the side exit rather than the rear exit.

    Sound master

    Reviewed by patrick h (ANAHEIM, CA) Reviewed for a 2015 GMC Sierra — Dec 07, 2017 8:03 PM

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    Sounds great looks better and easy to install

    Looks good sounds good

    Reviewed by Gary S (Altura, MN) Reviewed for a 2017 GMC Sierra — Aug 11, 2017 6:07 PM

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    A great product well made just need to be patient matching tailpipe positions and angles. Recommend you tack weld all joints then fully tighten clamps.

    2015 Silverado V6 Flow Master system

    Reviewed by Jon M (Richmond, RI) Reviewed for a 2015 Chevy Silverado — Jul 17, 2017 9:17 PM

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    Very simple to install, follow directions and tighten everything good. They look and sound great

    2014 GMC Sierra sle crew cab short bed

    Reviewed by Brian M (COOS BAY, OR) Reviewed for a 2014 GMC Sierra — Jun 20, 2017 8:59 PM

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    Nice easy install, wish it would have come with a new clamp to the cat, cause the hardware on the orginal was a little rusty


    Reviewed by Brian C (GRAND RAPIDS, MI) Reviewed for a 2014 Chevy Silverado — May 05, 2017 3:28 AM

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    The clamps are not the greatest. Went with aftermarket. The sound is not over bearing at cruising speeds. You definitely notice the rumble when you get on it thou.If you can keep your foot out of it, the MPG'S do go up.

    2017 Silverado Crew Cab

    Reviewed by Calvin B (HARTSVILLE, SC) Reviewed for a 2017 Chevy Silverado — May 04, 2017 4:44 AM

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    The install was fairly easy. However, (as previously stated in other reviews) I had to replace all of the supplied clamps with ones purchased from my local auto parts store and added 2 hangers (approx $35), because the supplied clamps are crap (which evidently they know about but keep including them for whatever reason), and t added 2 hangers near the tailpipes to prevent them from rattling. I have had Flowmaster exhausts on previous vehicles and the sound is good, Get stainless steel.

    Rumble in the Jungle

    Reviewed by Mike S (SPRINGFIELD, IL) Reviewed for a 2017 GMC Sierra — Apr 12, 2017 6:23 AM

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    The exhaust sounds great for my 2017 Sierra. Not too loud and cab noise only gets loud while cruising at 75+ but it's not overbearing. The installation wasn't too bad after I got a cheater bar to tighten the clamps. I also added a tuner super chip which is a must if you want to feel the true power your truck is capable of.

    America Thunder

    Reviewed by Brian F (WOODBURY, CT) Reviewed for a 2014 Chevy Silverado — Feb 28, 2017 7:28 AM

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    Exhaust system sounds great and was easy to install. I was disappointed with the clamps that came with it since they did not tighten down enough to hold the pipes in place. For a $750 system everything included should work as intended. I had to go to the auto parts store and purchase 5 cheap clamps as replacements. Other than that I would recommend the system.

    FLowmaster American THunder

    Reviewed by Joshu S (CICERO, NY) Reviewed for a 2016 Chevy Silverado — Feb 09, 2017 7:41 AM

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    Great product, with excellent warranty, and price from autoanything.