Upgrade the sound and performance of your heavy-duty truck with the Flowmaster American Thunder Cat-Back Exhaust System, engineered specifically for 2011–2019 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD models equipped with the 6.0L engine. This system delivers a powerful moderate-to-aggressive exhaust tone both inside and outside the cabin, enhancing your truck’s driving experience while maintaining emissions legality.

This bolt-on exhaust system is designed for Crew Cab Standard Bed (6.5 ft) configurations with a 153.7-inch wheelbase. It features a durable stainless steel 50 Series HD muffler, dual 3.00-inch mandrel-bent tailpipes, and the option to run dual exits either straight out the back or out the sides. The system is finished with premium polished 4-inch stainless steel tips for a high-end look.

Using the factory hanger locations, installation is straightforward with no modifications required. The exhaust system is constructed from high-quality stainless steel and backed by Flowmaster’s Lifetime Limited Warranty.

Key Features

• Uses factory hanger locations
• 50 Series HD muffler with Delta Flow technology
• Multiple tailpipe exit configurations included
• Large 3.00-inch dual tailpipes
• High-quality stainless steel construction
• Polished 4-inch stainless steel tips
• Emissions-legal and bolt-on installation
• Lifetime Limited Warranty
• Signature Flowmaster sound and performance

Specifications

• Category: Exhaust
• Clamping Type: Flat Band
• Clamps Included: Yes
• Drive Type: 2WD
• Emission Code: 5
• Exhaust Series: American Thunder
• Exhaust Tip Color: Silver
• Exhaust Tip Connection: Clamp-On
• Exhaust Tip Diameter: 4.00 in
• Exhaust Tip Finish: Polished
• Exhaust Tip Length: 13.00 in
• Exhaust Tip Material: 304 Stainless Steel
• Exhaust Tip Quantity: 2
• Exhaust Tip Shape: Round
• Exhaust Tip Wall: Double Wall
• Exit Style: Dual Out Rear
• Finish: Natural
• Gasket or Seal Included: No
• Hangers Included: Yes
• Inlet Diameter: 3.50 in
• Inlet Type: Flanged
• Main Piping Diameter: 4.00 in
• Mounting Bracket Included: Yes
• Muffler Body Height: 5.00 in
• Muffler Body Length: 18.25 in
• Muffler Body Material: 409 Stainless Steel
• Muffler Body Shape: Oval
• Muffler Body Width: 10.00 in
• Muffler Finish: Black High-Temperature Paint
• Muffler Inlet: Slip-Fit
• Muffler Inlet Inside Diameter: 3.50 in
• Muffler Outlet Quantity: 2
• Muffler Series: 50 Series HD
• Muffler Type: Chambered
• Pipe Color: Silver
• Pipe Material: 409 Stainless Steel
• Sound Level: Aggressive / Moderate
• Tail Pipe Outlet Diameter: 3.00 in
• Tail Pipe Quantity: 2
• Tail Pipe Tapered Outlet: No
• Type: Cat-Back
• Valve Included: No

Fitment 

Compatible Vehicles:
• 2011 Chevrolet Silverado 2500HD 6.0L
• 2012 Chevrolet Silverado 2500HD 6.0L
• 2013 Chevrolet Silverado 2500HD 6.0L
• 2014 Chevrolet Silverado 2500HD 6.0L
• 2015 Chevrolet Silverado 2500HD 6.0L
• 2016 Chevrolet Silverado 2500HD 6.0L
• 2017 Chevrolet Silverado 2500HD 6.0L
• 2018 Chevrolet Silverado 2500HD 6.0L
• 2019 Chevrolet Silverado 2500HD 6.0L
• 2011 Chevrolet Silverado 3500HD 6.0L
• 2012 Chevrolet Silverado 3500HD 6.0L
• 2013 Chevrolet Silverado 3500HD 6.0L
• 2014 Chevrolet Silverado 3500HD 6.0L
• 2015 Chevrolet Silverado 3500HD 6.0L
• 2016 Chevrolet Silverado 3500HD 6.0L
• 2017 Chevrolet Silverado 3500HD 6.0L
• 2018 Chevrolet Silverado 3500HD 6.0L
• 2019 Chevrolet Silverado 3500HD 6.0L
• 2011 GMC Sierra 2500HD 6.0L
• 2012 GMC Sierra 2500HD 6.0L
• 2013 GMC Sierra 2500HD 6.0L
• 2014 GMC Sierra 2500HD 6.0L
• 2015 GMC Sierra 2500HD 6.0L
• 2016 GMC Sierra 2500HD 6.0L
• 2017 GMC Sierra 2500HD 6.0L
• 2018 GMC Sierra 2500HD 6.0L
• 2019 GMC Sierra 2500HD 6.0L
• 2011 GMC Sierra 3500HD 6.0L
• 2012 GMC Sierra 3500HD 6.0L
• 2013 GMC Sierra 3500HD 6.0L
• 2014 GMC Sierra 3500HD 6.0L
• 2015 GMC Sierra 3500HD 6.0L
• 2016 GMC Sierra 3500HD 6.0L
• 2017 GMC Sierra 3500HD 6.0L
• 2018 GMC Sierra 3500HD 6.0L
• 2019 GMC Sierra 3500HD 6.0L

Note: Fits Crew Cab with 6.5-foot bed and 153.7-inch wheelbase only.

This system delivers the sound, durability, and performance enhancements expected from Flowmaster, making it a reliable upgrade for your heavy-duty truck.