Description
Overview
The Flowmaster American Thunder Cat-back Exhaust System transforms the exhale of your GM truck with a deep, powerful tone and a genuine performance upgrade you can bolt on at home. Engineered for 2007-2013 GM Silverado/Sierra 1500 models equipped with the 5.3L engine, this complete cat-back kit is built for the driver who wants a moderately aggressive sound both inside and outside the cab without crossing into unbearable drone territory.
At the heart of the system is a Super 40 Series muffler, tuned to deliver Flowmaster’s signature deep, powerful sound. Feeding that muffler is 3.00-inch mandrel-bent stainless steel tubing, engineered to promote smooth flow, while the 2.50-inch mandrel-bent stainless steel tailpipes carry the exhale rearward. Every component is designed to work together as a matched kit, so you get a cohesive tone and a clean, professional-looking installation.
Choose Your Exit
One of the best features of the American Thunder system is its flexible tailpipe routing. You can configure the dual tailpipes to exit straight out the back under the bumper for a muscular, aggressive look, or route them out behind the rear tires on each side of the truck. That side-exit setup is the ideal choice when towing a boat or RV, keeping the exhaust flow clear of your trailer. Both configurations are finished with large 3.50-inch double wall polished stainless steel tips featuring an embossed logo for a premium appearance that stands up to the elements.
Key Highlights
- 3.00-inch mandrel-bent stainless steel tubing into a Super 40 Series muffler for a deep, powerful sound
- Dual 2.50-inch mandrel-bent stainless steel tailpipes with your choice of rear or side exit
- Large 3.50-inch double wall polished stainless steel tips with embossed logo
- Flanged, bolt-on design that includes all necessary parts and hardware
- Emissions-legal and CARB (California) compliant
- Backed by Flowmaster’s Lifetime Limited Warranty
Fitment
This American Thunder cat-back is engineered for 2007-2013 GM Silverado/Sierra 1500 trucks with the 5.3L engine, fitting both 2- and 4-wheel-drive models with 143.5 and 157.5-inch wheelbases. It also fits 2007-2008 GM Silverado/Sierra 1500 models with the 4.8L engine and the same 143.5 and 157.5-inch wheelbases. Please note this kit does not include a heat shield.
With mandrel-bent stainless construction, a proven Super 40 muffler, configurable exits, and a straightforward bolt-on installation, the Flowmaster American Thunder gives your Silverado or Sierra the muscular sound and finished look it deserves — all while remaining emissions-legal for California and beyond.
