Flowmaster is pleased to release their latest FlowFX cat-back exhaust system for 1999-2007 Classic Body GM Silverado/Sierra 1500 trucks with 4.3L, 4.8L and 5.3L engines. These systems enhance looks, performance, and sound alike. Featuring 409SS construction and 16-gauge mandrel-bent tubing, these FlowFX systems boast improved durability and unrestricted flow over stock. As a result of the system design, the installation of this kit yielded 6.7 hp and 6.5 ft/lbs or torque on our development vehicle.

The compact, oval "straight-through" FlowFX performance muffler attaches behind the catalytic converter and delivers a moderate, deep and powerful sound with minimal interior resonance. The mandrel-bent stainless tailpipe tucks up high in the undercarriage protecting it from being crushed when traversing rocky terrain.

The system fits extended cab 6.5’ bed trucks as well as the crew-cab trucks with 5.5’ beds that feature a 143.5’’ wheelbase.

Factory hanger locations are utilized and the system is finished off with a 4.5" black ceramic-coated 304SS tip embossed with the Flowmaster name. The kit includes detailed instructions and all hardware necessary for a quick and easy installation you can do at home. It is also supported by Flowmaster’s Lifetime Limited Warranty.