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Flowmaster American Thunder Cat-Back Exhaust - Muffler Relocate (07-17 Wrangler JK)

Market Price $509.99 You Save 13% ($67.02)
Our Price

$442.97 (kit)

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  • Item J100311
  • MPN# 817674

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Features, Video & Details

  • Cat-Back System
  • 409 Stainless Steel
  • Polished Finish
  • Made in the USA
  • Moderate to Aggressive Tone
  • 2.5 Inch Mandrel-Bent Tubing
  • Increased Off-Road Ground Clearance
  • Laminar Flow Super HP-2 Muffler
  • Limited Lifetime Warranty
  • Fits 2007 - 2017 JK Wranglers

Review & Installation Video

Review & Install Video

I'm Ryan with ExtremeTerrain.com, and this is my review of the Flowmaster American Thunder Catback exhaust system with muffler relocation, fitting all 2007 or 2016 Wranglers. This system will fit both two-door and four-door JKs. You should be taking a look at this exhaust system if you're looking for a little bit more sound out of your JK. This system will provide a lower and a louder exhaust sound. And something I really like about this Catback system over a lot of the axle-back systems that are available on the market is that this will completely relocate the muffler up and out of the way of rocks and other trail hazards. So if you've damaged your factory system and you're looking for a replacement, or you just want that lower, louder exhaust note, this is a good system to take a look at. Flowmaster built this out of 409 stainless, which is a quality stainless steel, but it's not going to quite give you the same corrosion resistance as a 304 stainless. So if you live in an area where they use a lot of salt on the road in the winter, like we do, you might still end up with some corrosion or surface rust with a system like this. All of the tubing is two and a half inch mandrel bent tubing, so you won't have any restriction on the bends, and the whole system is finished off with this nice polish tip. The heart of this system is the laminar flow Super HP-2 muffler. This gives you all of the flow and the sound of the HP-2 muffler in this compact square case, which is nice, because, like we said before, this tucks the muffler up out of the way of the trail hazards so it's not going to get damaged. When you take the system out of the box, you can tell that it is well-built and well-designed, even if the welds on the muffler leave a little bit to be desired, at least visually. Nice thing about this system is that Flowmaster backs you with a limited warranty. You can install this system at home in your driveway. Just keep in mind that the same system is sold for both four-door and two-door JKs, so if you're installing it on a two-door, you will have some cutting to do. The install instructions tell you exactly where to cut and how much. However, after we made that cut, we found that they told us to take off a little bit too much. We also had to do some additional trimming that wasn't in the installation instructions to get our system to fit right. So if you're not comfortable doing that type of cutting and fitting, I would recommend that you take the Jeep to an exhaust shop to have them install the system. If you do decide to install this system yourself, there are a couple things to keep in mind. As with any exhaust system installation, the install time will vary greatly depending on how rusty your stock system is. I would definitely recommend spraying all of the stock clamps and bolts with a good penetrating oil well before you get started. That will definitely speed things up. And those of you who have done exhaust systems in the past will know that the rubber exhaust hangers can be a little bit tricky. I would also recommend lubricating those and having a pry bar handy to pop them loose. This is a high-clearance exhaust system, so it tucks everything up out of the way, and clearance is a little bit tight in some spots. One spot in particular, where the new tubing runs between the sway bar and the rear cross member, is particularly tight. We were able to get our system adjusted so it didn't hit either the cross member or the sway bar, but it took some patience. With the additional trimming and the fine tuning, the entire installation should take about two hours. Once we got this system installed and out on the road, I have to say I really liked the way it sounded. It's definitely a lower exhaust note, and you get a little bit more volume, but you don't get a drone in the cab, which is really nice. We even got a little bit of popping and gurgling during engine braking with our stick shift. This system doesn't just sound good, it's also functional. It tucks everything up out of the way of trail obstacles and rocks. I have to say I do like the way it sounds and the way it functions. But I would have like to see it fit a little bit better right out of the box, especially for a system at this price point. Now there are exhaust systems that we offer that are more expensive, and they don't relocate the muffler, so I would say this is a really good value once you get it installed. So if you're looking for an exhaust system that will give you a lower and louder exhaust note, and tuck all the exhaust components up out of the way of trail obstacles, I would say this is a good choice, even if the install was a little bit challenging. That's my review of the Flowmaster American Thunder Catback exhaust system with muffler relocate, fitting all 2007 and 2016 JKs that you can find right here at ExtremeTerrain.com.

Construction. Flowmaster's American Thunder Cat-back exhaust system is constructed out of 409 stainless steel for lasting durability. This American made system features a 2.5 inch round, mandrel bent tubing for smooth, unrestricted airflow. Combined with Flowmaster's Patented Laminar Flow Muffler, this system will give your JK a throaty and aggressive tone. This system improves your JK's ground clearance by relocating the muffler up and out of the way of rocks and trail hazards. Experience the trails while enjoying your rig's new sound!

Application. Flowmaster protects their stainless steel systems with a limited lifetime warranty. This system fits 2007 - 2017 Jeep Wrangler JK Models.

Fitment: 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 Details

What's in the Box
  • (1) Inlet Pipe Assembly
  • (1) Muffler
  • (1) Over Axle Pipe
  • (1) Exit Pipe Assembly
  • (1) Clamp & Hanger Kit
Installation Info
Will it fit my Wrangler?
  • JK - 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17
  • JK Unlimited - 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17
  • JK Rubicon - 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17

People Who Bought This Item Also Bought

Most Helpful Reviews

5/5
Sounds Awesome

This exhaust sounds great, it has a deep full sound in low rpms and in high rpms it has a higher tone. Absolutely love this exhaust. It is a little louder than the video shows but is a perfect balance. ...

Read More
Helpful (1)

5/5
Awosome muffler

Easy to install 2 1/2 hours to do it,very good sounds and more power.

Helpful (1)

Overall Rating 4.6 out of 5 stars
Read All 19 Reviews

Customer Photos (4) Submit Your Photo

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2 Questions / 2 Answers

Ask a Question

I reall like this system for my 2016 Jeep Wrangler jk but my question is will pass inspection without the catalytic converter

KevinW

  • The Flowmaster American Thunder Cat Back Exhaust will install after the stock cat, allowing you to retain all emissions equipment and pass inspection.

    Rob D

Helpful (1)

Will this fit a 2017 Rubicon?

CrisS

  • Hello! The Flowmaster American Thunder Cat Back Exhaust will fit a 2017 Rubicon.

    VinceXT

Helpful (0)

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Customer Reviews (19) Write a Review

Overall Rating 4.6

out of 5 stars

Installation Time:Afternoon

Installation Cost:0-$100

  • Exhaust Note 4.421052 4.4
  • Fit & Finish 4.368421 4.4
  • Bang For Your Buck 4.631579 4.6



  • 5/5

    Installation Time: Afternoon

    June 16, 2017

    Sounds Awesome

    This exhaust sounds great, it has a deep full sound in low rpms and in high rpms it has a higher tone. Absolutely love this exhaust. It is a little louder than the video shows but is a perfect balance. Keep in mind that if you have a rusted exhaust it will take a while to get off.

    TimothyM

    Year: 2008Submodel: Wrangler

    Helpful (1)

  • 3/5

    Installation Time: Less than 1 Hour

    June 11, 2017

    Flowmaster Exhaust

    I installed this product about week ago. If you have minor automotive skills, you can install it. There are detail videos out there on how to install the exhaust system.I installed it in about 45mins. I like the sound of the exhaust, but it might be to loud for some persons. But on a good note, my gas mileage has increased by 3 miles per gallon.

    WhiteWolf

    Year: 2016Submodel: Wrangler

    Helpful (1)

  • 5/5

    October 26, 2016

    Awosome muffler

    Easy to install 2 1/2 hours to do it,very good sounds and more power.

    Bejo

    Year: 2014Submodel: Rubicon Unlimited

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    October 04, 2016

    Flowmaster exaust install

    Everything went smooth on the install.just had to cut about 1 inch off the pipe after the muffler to get it to fit properly. Sounds great.

    Bikenut61847

    Year: 2016Submodel: Rubicon

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    August 03, 2016

    Awesome.

    Very easy to install. The hardest part was getting the old exhaust out. Sounds killer also.

    Giveumtheboot

    Year: 2011Submodel: Rubicon Unlimited

    Helpful (1)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    February 20, 2014

    Flowmaster thunder

    My factory exhausted had rotted out so it was time for a replacement, always liked flowmaster as I've had them on pickups and my grand national. Went with the thunder series as it was cheaper than the super 50 style plus it was very low profile. Install went well, with some very tight clearances, we spaced the rear swaybar away from the frame with some barstock steel to give us a little space. Nice tight fit with no vibrations. The exhaust is a little louder than I thought it would be but it is not ricey or tinny sounding. All in all a good flowmaster product.

    Rs464

    Year: 2008Central NH

    Helpful (1)

  • 4/5

    Installation Time: Full Day

    August 16, 2017

    Great sound, tough install

    Love the sound of this muffler, love the clearance space. Installation was not as easy as suggested. I had to grind off a OEM screw on Y joint and cut 1/2" off pipe to make the pipe fit above the rear sway bar.

    DanC

    Year: 2017Submodel: Wrangler

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    August 16, 2017

    Great sounded exhaust

    Sounds awesome. Doesn't drone on the highway and overall isn't loud enough to be annoying. You get some nice tones when down shifting and lifting off the throttle also. Careful when making cuts if you have a 2 door.

    Phil

    Year: 2012Submodel: Wrangler

    Helpful (0)

  • 5/5

    Installation Time: Less than 1 Hour

    July 29, 2017

    Flowmaster

    Good product easy to install makes very nice sound happy with the product .

    FrankV

    Year: 2017Submodel: Wrangler

    Helpful (0)

  • 5/5

    July 08, 2017

    Flowmaster!!

    Was little concerned with all the different reviews and different manufacturers. Flowmaster does not disappoint. Sounds great, tight fit, (which I liked) bout 2 hrs to tear old out and install new. Good deal.

    ShawnF

    Year: 2010Submodel: Rubicon

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    June 26, 2017

    Flowmaster Cat Back Exhaust

    Installation required grinding down a small "nailhead" on stock system at the front end of the pipe installation. Alternatively the add-on pipe needs to be cut down even for JKU in order to make it fit perfectly on back end

    GeraldY

    Year: 2016Submodel: Rubicon

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    June 16, 2017

    Loud and proud

    It's loud, allot more than I expected, but it sounds good. Sounds allot like the old jeep 4.0 straight 6.

    Dan

    Year: 2014Submodel: Rubicon

    Helpful (0)

  • 4/5

    Installation Time: Afternoon

    April 17, 2017

    Sounds Brutal

    This is a great exhaust and sounds brutal but not obnoxious. Dies down once you finally get moving. It took me and a friend a while to get the old exhaust out and unfortunately I had to cut some of the new exhaust to make it fit. While it took some time and patience to get in. It fits nice and tight and I am happy with it. Plus I gained about 2 more MPG out it.

    LeopoldB

    Year: 2016Submodel: Wrangler

    Helpful (0)

  • 2/5

    Installation Time: Afternoon

    April 06, 2017

    Ehhhh

    The muffler itself sounds great but man it is a super tight squeeze and a pain in the butt to install. Also had to do more cutting to the new exhaust then instructed plus one of the hangers was resting on my transfer case so I had to torch that off. Very tight squeeze between the floor boards and seat bar too. Just needs to be designed different.

    ChrisF

    Year: 2011Submodel: Wrangler

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    April 05, 2017

    Flowmaster American Thunder Cat Back Exhaust

    Like others the install was fairly easy. I found mine was not lining up right and instead of cutting a little off (4 door) there is a metal index tab on the Y pipe that stops the new exhaust pipe from sliding far enough forward. Once I removed it the exhaust slide forward enough to allow everything to line up perfectly. As others stated it helps to drop the rear sway bar also. The exhaust fits like a glove once aligned properly.

    chilireds

    Year: 2015Submodel: Rubicon

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    March 29, 2017

    Good but...

    Ok let me start by saying this is an amazing exhaust system. It sounds great and is way out of the way from being damaged. That being said I installed it on a 2 door. The instructions say to cut 21 and a half inches off the second pipe. Like the other people I found on YouTube, cut only 20" off the second pipe and 2 inches off the first one. It also helps to drop the sway bar during installation. But once it's on it's awsome!

    ZakkaryU

    Year: 2016Submodel: Wrangler

    Helpful (0)

  • 4/5

    Installation Time: Afternoon

    March 21, 2017

    Great Sound

    Great product the install was a litlle tight and had to cut to make fit!

    Dan

    Year: 2017Submodel: Rubicon

    Helpful (0)

  • 5/5

    September 24, 2016

    Flowmaster American Thunder

    Removing the OEM exhaust was a bit of a chore (1/12 hour's), the Flowmaster took about 45 min. to install! Great sound thru the gears! Herb

    Herb

    Year: 2016Submodel: Wrangler Unlimited

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    September 18, 2015

    Flowmaster thunder

    Great bang for your buck and easy to install. My only complaint is that with my stock 3.6 it sounds a little bit like a Honda....but overall a great product.

    Phat

    Year: 2014KS

    Helpful (0)

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