Flowmaster American Thunder Cat Back Exhaust System - 817674


  • Flowmaster Exhaust | Part Number: FLW817674
  • Exit Location/Type:Single Turndown After Muffler
  • Material:Stainless Steel
  • System Type:Cat-Back
  • Tip Included:Tip is included
  • Tubing Size:2.5 Inches
  • Fitment:Direct Fit


Flowmasters new American Thunder cat-back system for the Jeep Wranglers is perfect for the person looking for maximum performance and ground clearance from their exhaust system. This 2.50" system features a 409S stainless steel mandrel bent tailpipe with a 3.00" polished stainless steel tip and fits both 2 and 4 door models with the 3.6L and 3.8L V6 engines. This system replaces the factory transverse muffler and relocates the Super HP-2 muffler behind the factory catalytic converter, providing a moderate to aggressive sound level. This relocation allows for better ground clearance when driving off-road. Because the tailpipe is tucked up so high, an aftermarket metal bumper is recommended. The exhaust system is manufactured in the USA and is covered by Flowmasters Lifetime Limited Warranty. Designed for an easy fit, this system includes all necessary parts and hardware for installation.



Installed on 2014 JK Rubicon X

So I installed this on a 2014 JKRX about a month ago and I have been waiting to post a review. The sound and ground clearance is awesome! My mileage has dropped 2 - 4 MPG and I am not driving it with a heavy foot due to the better sound of this system over stock. The install took way too long as it seemed that I was the first person (according to Flowmaster tech support) which struggled with a two-door install. I ended up cutting 1.75" off of the first pipe connected to the stock y-pipe to make it fit. The 3/4" clearance recommended by flowmaster is very difficult to achieve over the rear sway bar and below the body at the rear axle

from Denver, CO |

Question & Answers

3 Answered questions

Can you get a Black tip for this exhaust?

Asked by Paul from Morrisville, NC on

Hello Paul and thank you for your question! Flowmaster Exhaust American Thunder Cat Back Exhaust System will take a black tip in either flat or gloss black.

Answered by Nick from Morrisville, NC on

Can you get a Black tip for this exhaust?

Asked by Paul from Morrisville, NC on

Thanks for the inquiry Paul, the Flowmaster Exhaust American Thunder Cat Back Exhaust System part # FLW817674 unfortunately a black tip is not an option.

Answered by from Morrisville, NC on

Is this exhaust street legal in North Carolina? Chris 08 Jeep Wrangler Unlimited

Asked by Chris the Jeeper from Mebane, NC on

Hello Chris, the Flowmaster Exhaust American Thunder Cat Back Exhaust System part# FLW817674 is street legal in North Carolina. Thank you for your inquiry.

Answered by mikey from Mebane, NC on


For over 30 years, Flowmaster has been producing exhaust products to combat noise issues that first cropped up on race tracks in California. The question was how to reduce sound without compromising performance? Advanced engineering and ample testing set Flowmaster's product line apart from competitors and a few of their more noteworthy parts include chambered mufflers, laminar flow designs and high flow catalytic converters. We carry Jeep exhaust pipes, exhaust flanges and complete exhaust systems among other Flowmaster products. The company's patented technologies, innovative designs and focus on performance keep Flowmaster at the forefront of aftermarket exhaust manufacturers. Shop Flowmaster Exhaust Now