Click to enlargeFlowmaster American Thunder

Flowmaster 17421 American Thunder muffler.


2005 Mustang 4.0L.

2006 Mustang 4.0L.

2007 Mustang 4.0L

2008 Mustang 4.0L.

2009 Mustang 4.0L.

An over the axle design.

Aluminized finish.

2 1/2" inlet.

3 1/2 inch rolled edge, logo embossed, polished stainless tip.

Specially designed 5 inch by 10 inch muffler.

All welded construction. No stamped seams to blow out.

Chambered inside for noise cancelation. No fiberglass packing to blow out.

Easy to install, this American Thunder series system simply attaches to the stock system.

Remove the stock mufflers, install the Flowmaster American Thunder mufflers and you are ready to roar!

Flowmaster 17421 2005-2009 Mustang 4.0 muffler FLOWMASTER-17421$255.97APPLICATIONS:: 

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