aFe Rebel Series 3in to 2.5in 409 SS Cat-Back Exhaust w/ Black Tips 09-18 GM Silverado/Sierra 5.4LaFe Rebel Series 3in to 2. 5in 409 SS Cat Back Exhaust w Black Tips 09 18 GM Silverado Sierra 5. 4L This Rebel Series exhaust is a dual, middle side exit system for the 2009 2018 GM Silverado Sierra 1500 Crew Cab Long Bed and delivers +14 horsepower and +17 lbs. x ft. of torque as measured on our in house dyno. 3" into dual 2 1 2" mandrel bent stainless steel tubing and high flow muffler offers maximum flow, increases horsepower and torque while