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Flowmaster Flow FX Catback Exhaust System GMC 2500HD | 3500HD 6.6L Gas 2020-2022

Flowmaster Flow FX Catback Exhaust System GMC 2500HD | 3500HD 6.6L Gas 2020-2022

Regular price $775.95 USD
Regular price $863.00 USD Sale price $775.95 USD
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Flowmaster Flow FX Catback Exhaust System GMC 2500HD | 3500HD 6.6L Gas 2020-2022


SKU: 718111

This Flowmaster FlowFX cat-back exhaust system for the 2020-2022 GM 2500HD/3500HD trucks with the 6.6-liter gas engine is manufactured using durable 409 stainless steel throughout and features 3.50 to dual 3.00-inch mandrel bent pipes for better exhaust gas flow, and a FlowFX "straight-through" muffler is used for a moderate sound level and maximum performance.

Maximum increases on the dyno revealed +9 hp and +10 lb-ft at the rear wheels. This system exits out both sides, behind the rear wheels with 4.50-inch black ceramic tips for added style and a custom look. The system uses all the existing factory hanger locations and includes installation instructions and all necessary hardware for an easy installation that you can do at home. Backed by Flowmaster's Lifetime Limited Warranty.


  • Max increases of up to 9 hp and 10 lb-ft over the stock exhaust at the rear wheels
  • 3.50 to dual 3.00-inch mandrel bent 16-gauge 409 stainless steel tubing maximizes exhaust flow and improves durability
  • 4.50-Inch black ceramic coated tips add a custom look to the truck
  • Includes complete hardware and factory styled hangers in the stock locations for an easy installation
  • FlowFX "straight through" performance muffler delivers a deep, aggressive to moderate performance tone and improves exhaust flow


  • Brand: Flowmaster
  • Emission Code : 5
  • Exhaust Series: FlowFX
  • Exit Position: DOS
  • Mount Type: Uses Factory Hangers
  • Muffler Body Length (in): 18
  • Muffler Color: Natural
  • Muffler Finish: Brushed
  • Muffler Inlet Diameter: 3.50
  • Muffler Inlet Diameter (in): 3.50
  • Muffler Inlet Location: Centered
  • Muffler Material: 409S Stainless Steel
  • Muffler Outlet Diameter: 3.00
  • Muffler Outlet Diameter (in): 3.00
  • Muffler Outlet Location: Dual Outlet
  • Muffler Overall Length (in): 24
  • Muffler Part Number: Kit Only
  • Muffler Quantity: 1
  • Muffler Series: FlowFX
  • Muffler Shape: Oval
  • Muffler Type: Absorption
  • Product Type: Exhaust System
  • Single Dual: Dual
  • Sound Level: Moderate
  • System Type: Cat-back
  • Tip Cut : Angle
  • Tip Diameter: 4.50
  • Tip Edge Style: Rolled
  • Tip Finish: Black Ceramic
  • Tip Length: 11
  • Tip Logo: Embossed
  • Tip Material: 304 Stainless
  • Tip Quantity: 2.00
  • Tip Shape: Round
  • Tip Style: Single Wall
  • Tubing Diameter (in): 3.00
  • Tubing Material: 409S Stainless Steel
  • UPC: 090127130155
  • California Proposition 65 Chemical Name: Chromium (hexavalent compounds) and Nickel (Metallic)
  • California Proposition 65 Required: Yes
  • Part Number: 718111

Vehicle Fitment:

  • 2020 GMC 2500HD | 3500HD
  • 2021 GMC 2500HD | 3500HD
  • 2022 GMC 2500HD | 3500HD


Product image for illustration purposes only. Actual product may vary.

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