Our American Thunder cat-back exhaust system for 2007-2013 GM Silverado/Sierra 1500 with the 5.3L engine, is perfect for the person looking for moderately aggressive sound levels both inside and outside of the truck. This bolt-on emissions-legal system features 3.00 in. mandrel-bent stainless steel tubing flowing into a Super 40 Series muffler, for a deep powerful sound. The mandrel-bent 2.50 in. stainless steel tailpipes can be configured with your choice of exit locations, either straight out the back under the bumper for a muscular look, or exiting out behind the rear tires on each side of the truck. This is the ideal tailpipe location when towing a boat or RV. The tailpipes are finished off with large 3.50 in. double wall polished stainless steel tips. The system includes all necessary parts and hardware for an easy installation and is covered by our Lifetime Limited Warranty. Notes: Fits all 2/4 wheel drives with 143.5 and 157.5 in. wheelbases. Also fits 2007-2008 GM Silverado/Sierra 1500 with 4.8L engines and 143.5 and 157.5 in. wheelbases.