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Flowmaster

Flowmaster 818206 American Thunder Cat-Back Exhaust System

Flowmaster 818206 American Thunder Cat-Back Exhaust System

Regular price $1,599.95 USD
Regular price Sale price $1,599.95 USD
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Description & Features

Flowmaster 818206 American Thunder Cat-Back Exhaust System

Flowmaster's® American Thunder® Cat-back exhaust system for the 2024 to 2026 GM 1500 trucks with the 6.2-liter engine is a great way to customize your Silverado or Sierra to your personality. This performance exhaust system fits both 2/4 Wheel drive models and is manufactured from 409 stainless steel for years of trouble-free service and performance. Features include a 3.50-inch inlet pipe leading into a specialty tuned 50 Series HD style muffler for great sound and maximum performance. This cat-back system has dual 2.5-inch mandrel-bent tailpipes that exit in the bumper cut-out locations, with custom quad exit 4.0-inch black ceramic tips for a great performance look. Included in this cat-back system is active valve control with an integrated turndown. This allows you to control the factory valve from the dash with the different drive modes for full control of your sound level. Run the valve closed in the Normal drive mode, or open the valve in Sport or Off-Road mode for maximum sound. Max dyno gains of 15 hp and 13 lb-ft at the rear wheels deliver power you can feel. These systems use all the factory hanger locations and connections for an easy installation that you can do at home. Kit include installation instructions and all necessary hardware. Backed by Flowmaster's Lifetime Limited Warranty.

  • 5 and 2.5-inch mandrel bent 16-gauge 409 stainless steel tubing maximizes exhaust flow and improves durability
  • Kit includes complete hardware and factory styled hangers in the stock locations for an easy installation
  • An tuned 50 Series HD style chambered muffler delivers a deep, aggressive to moderate performance tone and improves exhaust flow
  • Max increases of up to 15 hp and 13 lb-ft over the stock exhaust at the wheels
  • Tuned performance muffler with built in resonance chamber eliminates interior drone
  • Lifetime Limited Warranty
Specifications
Brand Flowmaster
California Proposition 65 Yes
California Proposition 65 Chemical Name Nickel (Metallic)
CARB (California) Compliant Yes
Catalytic Converter Included No
Catalytic Converter Quantity 0
Category Exhaust
Choose Your Part Exhaust System
Clamping Type Flat Band
Clamps Included Yes
Drive 2WD
Emission Code 5
Exhaust Series American Thunder
Exhaust Tip Color Black
Exhaust Tip Connection Clamp-On
Exhaust Tip Cut Angled
Exhaust Tip Diameter 4.00
Exhaust Tip Edge Rolled Edge Angle Cut
Exhaust Tip Finish Black Ceramic Coating
Exhaust Tip Intercooled No
Exhaust Tip Length 7.5
Exhaust Tip Material 304 Stainless Steel
Exhaust Tip Quantity 2
Exhaust Tip Resonated No
Exhaust Tip Shape Round
Exhaust Tip Wall Double Wall
Exit Style Dual Out Rear
Finish Natural
Gasket Or Seal Included No
Grade Type Performance
Hangers Included Yes
Heat Shield Included No
Inlet Diameter 3.50
Inlet Type Clamp-On
Main Piping Diameter 2.50
Mount Type Uses Factory Hangers
Mounting Bracket Included Yes
Muffler Body Height 5.00
Muffler Body Length 18.00
Muffler Body Material 409 Stainless Steel
Muffler Body Shape Oval
Muffler Body Width 10.00
Muffler Color Black
Muffler Finish Black High-Temperature Paint Finish
Muffler Flanged Inlet No
Muffler Flanged Outlet No
Muffler Included Yes
Muffler Inlet Connection Slip-Fit
Muffler Inlet Inside Diameter 3.5
Muffler Inlet Location Offset
Muffler Inlet Outside Diameter 3.63
Muffler Outlet Connection Slip-Fit
Muffler Outlet Diameter 2.50
Muffler Outlet Location Dual
Muffler Outlet Quantity 2
Muffler Part Number Kit Only
Muffler Quantity 1
Muffler Series 50 Series HD
Muffler Type Chambered
part type Exhaust System
Pipe Color Silver
Pipe Material 409 Stainless Steel
Product Type Exhaust System
Sound Level Aggressive / Moderate
Spring Bolt Kit Included No
Tail Pipe Outlet Outside Diameter 2.50
Tail Pipe Quantity Dual
Tail Pipe Tapered Outlet No
Type Cat-Back
Valve Actuator Included No, Reuse OEM
Valve Included Yes
Valve Type OEM-Style Valves
Warning California Proposition 65
Packaging Information

Weight: 75.5 lbs
Dimensions: 62.5 x 18 x 14.75 IN

Safety

⚠ WARNING: This product can expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information visit www.P65Warnings.ca.gov

Warranty

View Warranty (PDF)

Installation Instructions

View Installation Instructions (PDF)

⚠ Fitment Notes
  • Fits trucks with factory bumper cut-outs only
  • Only fits models with bumper exhaust bezels.

Vehicle Fitment

  • 2024-2026 Chevrolet Silverado 1500 High Country
  • 2024-2026 Chevrolet Silverado 1500 LT Trail Boss
  • 2024-2026 Chevrolet Silverado 1500 LTZ
  • 2024-2026 Chevrolet Silverado 1500 RST
  • 2024-2026 GMC Sierra 1500 AT4
  • 2024-2026 GMC Sierra 1500 Denali
  • 2024-2026 GMC Sierra 1500 Denali Ultimate
  • 2024-2026 GMC Sierra 1500 SLT
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California Proposition 65 Warning

This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov ↗.