Flowmaster Axle-Back Exhaust System American Thunder With 4" Tips Mustang GT 2013-2014
Flowmaster American Thunder Axle-Back Exhaust System with 4" Tips for all 2013-2014 GT Mustangs.
Do you want to give your 2013-2014 GT Mustang an aggressive sound and increased performance? This American Thunder Axle-Back Exhaust System with 4" Tips from Flowmaster will deliver gains in both of those departments!
Features and Benefits of the Flowmaster American Thunder Axle-Back Exhaust System with 4" Tips (817588):
- Provides aggressive sound
- Increases performance levels
- Made of premium stainless steel
- Super 44 series mufflers with polished 4" tips
- Dual rear exhaust
- Direct-fit replacement
- 3" tubing with a 2-3/4" inlet
- Dyno tuned for maximum performance
- Patented Delta Flow technology
- Easy to install
Flowmaster designs the American Thunder exhaust systems to provide aggressive sounds and enhanced performance levels thanks in part to the dyno tuned, patented Delta Flow technology. This system is constructed out of T409 stainless steel and features specially modified Super 44 series mufflers with polished 4" tips. This axle-back exhaust system has 3" tubing with a 2-3/4" inlet, making it a direct bolt-on replacement exhaust for your GT Mustang!
Flowmaster is a manufacturer of just about any part you need for your Mustang's exhaust, from full exhaust systems and exhaust kits, to mufflers and accessories. Flowmaster is widely known for its distinctive 'Flowmaster sound,' which is available in mild, moderate and aggressive tones.
Order Flowmaster's 817588 American Thunder Axle-Back Exhaust System with 4" Tips for your 2013-2014 GT Mustang from CJ Pony Parts today!
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Related Categories: Mustang Parts, Mustang Exhaust, Mustang Axle Back Exhaust Kits
Installation Difficulty

Novice skill is required for this installation.
Installation Videos
Video Transcript
Alex: Thank you for having me Bill. How are you doing today?
Bill: I'm doing good. We all know the two chamber Flowmaster. If you had a Fox Body back in the day you had some Flowmasters on it. But what else can you tell us about your company?
Alex: Well, Flowmaster is an aftermarket performance exhaust manufacturer, Bill, that started off on the racetracks. Ray Flugger, the founder of the company, designed mufflers for racers that were being hammered for excessive noise limits. Flowmaster presents that opportunity where you're able to reduce those dB levels without having to hurt or kill performance. Flowmaster is also one of the most significant speed parts of all time where we are actually an innovative product different from the standard that's out there.
Bill: The two chamber Flowmaster that was the original product he was selling out of a suitcase.
Alex: The 40 Series, except with some slight modifications on the case itself. Back then it was a square case and now it's more of a round oval.
Bill: The other mufflers you have here, what can you tell me about them?
Alex: Here we have a 50 Series Delta Flow to the far right, which is a three chamber design, a little more subdued, a little mellower for those that are looking for less interior resonance. In the middle here we've got a Super 40, which is a two chamber design, a little thicker, a little wider, which is set up to handle higher output applications. To the far left we've got a Super 44, which is the latest and greatest two chamber design that Flowmaster has released in recent years.
Bill: Is that still based off of the original design?
Alex: That is correct.
Bill: I know Flowmaster has a lot of kits available for the 2005 and newer Mustangs. What can you tell me about these two kits you brought with you today?
Alex: Well, Bill here we've got a Force II exhaust system from Flowmaster. It's a direct bolt on axle back 409 stainless steel with a limited lifetime warranty, fully constructed here in the U.S. It's got the rolled edge stainless steel tip with the nice four inch diameter. All of the hardware, everything you need, is included within the kit so you don't have to buy any additional accessories.
This would probably take you an hour and a half to install out of your own garage on a weekend. Very subdued, very mellow kind of tone, something designed for someone who's looking for more of a performance aspect with a little bit of rumble, nothing too wild, nothing too crazy.
Over here on the right we've got the Outlaw System. The Outlaw is very noticeable, very aggressive. It's the 'hear me from a mile away' type of sound, something I would only recommend to those who are fully aware of what they're getting. It utilizes an Outlaw race muffler, basically a muffler that was designed for race applications that are required to run mufflers without a specific dB limit. Again, I only recommend it to those that are looking for the aggressive tone from Flowmaster. It is fully built out of stainless steel, lifetime warranty as well.
Bill: The Outlaw is available for '05 and up for both the 5.0 liter and the 4.6 liter cars?
Alex: That is correct.
Bill: We know Flowmaster that has systems that fit all year Mustangs, but I heard you guys are getting in other parts of the exhaust as well?
Alex: That's right, Bill. We actually just released a full line of stainless steel headers, ceramic coated, very high end piece. They look great. It'll compliment the rest of your exhaust components. We also just released a full line of catalytic converters, both 49 state and carb certified.
Bill: If you're looking for that classic Flowmaster sound, it doesn't matter what year your car is, Flowmaster has a system that will fit your Mustang.







