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Exhaust System Kit

Flowmaster - American Thunder Axle Back Exhaust System (817588)

$498.95

$554.95

You save: $56.00 (10%) off MSRP

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This part fits

  1. 2014 Ford Mustang GT 5.0L V8 cid:302 cc:4951
  2. 2013 Ford Mustang GT 5.0L V8 cid:302 cc:4951
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About this product

Part #: 817588

American Thunder exhaust systems deliver the aggressive sounds you want, as well as the performance gains you demand. This T409 stainless steel American Thunder Axle-back for the 2013 to 2014 Mustang GT features specially modified Super 44 series mufflers with polished 4.00 in. stainless tips and is a direct bolt on for the restyled Mustang. A lifetime limited warranty provides assurance that this American made exhaust will deliver that famous Flowmaster sound for many years to come.

More Details

Exhaust SeriesAmerican Thunder
Exhaust TypeDual
Exit PositionDual Rear
Exit StyleStraight
Heat Shield AttachedNo
Inlet Diameter2.750 in.
Inlet Inside Diameter3.000 in.
MaterialStainless Steel
Muffler Count2
Muffler Part NumberKit Only
Muffler SeriesSuper 44 Series
Outlet Diameter3.000 in.
Outlet Outside Diameter4.000 in.
Single or DualDual
Sound LevelAggressive
System TypeAxle Back
Tail Pipe Diameter3.000 in.
Tip Diameter4.000 in.
Tip Quantity2
TitleFlowmaster 817588 Axle-back System 409S - Dual Rear Exit - American Thunder - Aggressive Sound
Tubing Diameter3.000 in.
Additional Documents
  1. Certificate of Originpdf
  2. Installation Instructionspdf
  3. Warrantypdf

See what our community says about flowmaster products

CeJay Innes-Mammen

371

CeJay Innes-Mammen
2006 Dodge Charger
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Prior experience with these mufflers on other HEMI's
Is this your first time buying from this brand? Did you consider other brands?
Long time patron
View on CeJay's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Got these for a deal of a GT in the local junkyard. Cheap and had everything I needed to fit to my car.
Is this your first time buying from this brand? Did you consider other brands?
Yes, but my dad has had Flowmasters before so between that and their excellent reputation I knew they were for me.
Was it easy to install? Any installation tips that will help others?
Somewhat difficult. Passenger side pipe would not go in the car even after loosening the shock mounts and letting it droop from the control arms. It had to be cut and welded in the car
Once you've had a chance to use the product, did it meet your expectations?
Yes, sounded excellent especially for a V6
View on Joey's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Wanted to try the single chamber muffler out
Is this your first time buying from this brand? Did you consider other brands?
No as I've always purchased Flowmaster
Once you've had a chance to use the product, did it meet your expectations?
Priced as usual for Flowmaster and I must say it's something you must experience yourself
View on Steven's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Sounded the best in my opinion. Very nice burble with stock exhaust manifolds and reasonable volume when you wind out the car. Just had a great muscle car sound in my opinion.
View on Jeffrey's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Classic Flowmaster sound.
Is this your first time buying from this brand? Did you consider other brands?
No, installed on other cars as well
Once you've had a chance to use the product, did it meet your expectations?
Nice sound and not too heavy on the wallet.
View on Tyler's build

MOST POPULAR Axle Back Exhaust

TOP RATED Flowmaster Exhaust

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*Some manufacturer restrictions apply.

About Flowmaster

Manufacturer of performance exhaust systems, mufflers, cold air intakes, turbo boost modules, catalytic converters, race mufflers, headers and numerous exhaust accessories for late model cars, trucks, off-road, Jeeps, SUV’s, classic muscle cars, powersports vehicles and more. Flowmaster® gives you lots of exhaust choices with 12 designs of chambered mufflers, 3 styles of our exclusive “laminar-flow” mufflers and a new line of FlowFX “straight-through” performance mufflers, along with 5 sound categories of exhaust systems, giving you the customer, the power to custom tailor the sound of your vehicle whether you prefer mild, moderate or aggressive tones and sound levels.

Benefits of adding this mod

An upgraded exhaust system is one of the easiest modifications that offers an immediate, noticeable performance improvement. Whether you’re cruising an M3 or modding a diesel truck, an upgraded exhaust will open up the restrictive factory system, allowing your engine to breathe better and deliver peak power! From lighter weight exhaust headers to improved cat-back systems, to better sounding mufflers, modifying your exhaust setup is a great place to express the character of your ride in a unique and cost effective way. Whatever you’re looking for in a modified exhaust system, we can provide the absolute best systems to make your vision a reality.

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we ship worldwide!

Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.

+ FREE GROUND SHIPPING ON U.S. ORDERS OVER $99
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Wheelwell helps you organize all your stuff for your car, I’ve loaded all my cars on Wheelwell and you can see all the parts I’ve put in them and that may help you make a decision with your own build.

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Matt Farah

Smoking Tire / The Drive

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Thank you for all the help, really. You guys are awesome. This is all great info and I really appreciate everything you have done to help me with my build.

James M.

Ford Focus ST

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Your customer service is wonderful. Thank you for taking care of this. My review will express all. Thank you!

Wallace R

Chevrolet Silverado 1500