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Flowmaster Flow FX® Cat-Back Exhaust System for 2020-2025 GM 2500HD/3500HD with 6.6L Gas Engine

Flowmaster Flow FX® Cat-Back Exhaust System for 2020-2025 GM 2500HD/3500HD with 6.6L Gas Engine

Flowmaster -

Regular price $949.95 USD
Regular price $1,068.95 USD Sale price $949.95 USD
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This Flowmaster® Flow FX® cat-back exhaust system for the 2020-2025 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 Flow FX "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. Fits 2020-2025 GM 2500HD/3500HD 6.6-Liter Gas, Cat-Back, Dual Side Exit, Stainless Steel Exhaust System 2020-2025 GM 2500HD/3500HD Trucks with 6.6-liter gas engines. Fits 2 & 4-wheel drive, Crew Cab with 6.5-foot bed only. Does not fit 5th wheel towing packages. Does not fit ZR2 and AT4X packages.
  • Flow FX “straight through” performance muffler delivers a deep, aggressive to moderate performance tone and improves exhaust flow
  • 3.50 to dual 3.00-inch mandrel bent 16-gauge 409 stainless steel tubing maximizes exhaust flow and improves durability
  • Includes complete hardware and factory styled hangers in the stock locations for an easy installation
  • Max increases of up to 9 hp and 10 lb-ft over the stock exhaust at the rear wheels
  • 4.50-Inch black ceramic coated tips add a custom look to the truck

Upgrade your 2020-2025 GM 2500HD or 3500HD truck with the Flowmaster Flow FX® cat-back exhaust system, engineered to enhance performance and style. Constructed entirely from durable 409 stainless steel, this system features 3.50-inch to dual 3.00-inch mandrel-bent pipes that promote superior exhaust gas flow, resulting in improved horsepower and torque. The inclusion of a Flow FX "straight-through" muffler provides a balanced sound profile—deep and aggressive yet moderate enough for everyday driving. Testing indicates gains of up to 9 horsepower and 10 lb-ft of torque at the rear wheels, making this system a notable upgrade for your vehicle. The dual side exit design with 4.50-inch black ceramic tips not only offers a custom aesthetic but also enhances exhaust flow and durability. The system utilizes factory hanger locations and includes all necessary hardware and installation instructions, allowing for straightforward installation at home. Backed by Flowmaster's Lifetime Limited Warranty, this exhaust system is designed to withstand the rigors of daily driving while providing improved performance and a bold look. Compatibility is confirmed for crew cab models with a 6.5-foot bed, excluding 5th wheel towing packages, ZR2, and AT4X variants. The system's installation does not require any modifications to the vehicle's existing components, making it a practical upgrade for truck enthusiasts seeking increased power and a distinctive exhaust note. The combination of high-quality materials and precise engineering ensures longevity and optimal performance, making this system a reliable choice for your heavy-duty truck.

Features:

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

Fitments:
2020 Chevrolet Silverado 2500 HD Custom
2020 Chevrolet Silverado 2500 HD High Country
2020 Chevrolet Silverado 2500 HD LT
2020 Chevrolet Silverado 2500 HD LTZ
2020 Chevrolet Silverado 2500 HD WT
2020 Chevrolet Silverado 3500 HD High Country
2020 Chevrolet Silverado 3500 HD LT
2020 Chevrolet Silverado 3500 HD LTZ
2020 Chevrolet Silverado 3500 HD WT
2020 GMC Sierra 2500 HD AT4
2020 GMC Sierra 2500 HD Base
2020 GMC Sierra 2500 HD Denali
2020 GMC Sierra 2500 HD SLE
2020 GMC Sierra 2500 HD SLT
2020 GMC Sierra 3500 HD AT4
2020 GMC Sierra 3500 HD Base
2020 GMC Sierra 3500 HD Denali
2020 GMC Sierra 3500 HD SLE
2020 GMC Sierra 3500 HD SLT
2021 Chevrolet Silverado 2500 HD Custom
2021 Chevrolet Silverado 2500 HD High Country
2021 Chevrolet Silverado 2500 HD LT
2021 Chevrolet Silverado 2500 HD LTZ
2021 Chevrolet Silverado 2500 HD WT
2021 Chevrolet Silverado 3500 HD High Country
2021 Chevrolet Silverado 3500 HD LT
2021 Chevrolet Silverado 3500 HD LTZ
2021 Chevrolet Silverado 3500 HD WT
2021 GMC Sierra 2500 HD AT4
2021 GMC Sierra 2500 HD Base
2021 GMC Sierra 2500 HD Denali
2021 GMC Sierra 2500 HD SLE
2021 GMC Sierra 2500 HD SLT
2021 GMC Sierra 3500 HD AT4
2021 GMC Sierra 3500 HD Base
2021 GMC Sierra 3500 HD Denali
2021 GMC Sierra 3500 HD SLE
2021 GMC Sierra 3500 HD SLT
2022 Chevrolet Silverado 2500 HD Custom
2022 Chevrolet Silverado 2500 HD High Country
2022 Chevrolet Silverado 2500 HD LT
2022 Chevrolet Silverado 2500 HD LTZ
2022 Chevrolet Silverado 2500 HD WT
2022 Chevrolet Silverado 3500 HD High Country
2022 Chevrolet Silverado 3500 HD LT
2022 Chevrolet Silverado 3500 HD LTZ
2022 Chevrolet Silverado 3500 HD WT
2022 GMC Sierra 2500 HD AT4
2022 GMC Sierra 2500 HD Base
2022 GMC Sierra 2500 HD Denali
2022 GMC Sierra 2500 HD SLE
2022 GMC Sierra 2500 HD SLT
2022 GMC Sierra 3500 HD AT4
2022 GMC Sierra 3500 HD Base
2022 GMC Sierra 3500 HD Denali
2022 GMC Sierra 3500 HD SLE
2022 GMC Sierra 3500 HD SLT
2023 Chevrolet Silverado 2500 HD Custom
2023 Chevrolet Silverado 2500 HD High Country
2023 Chevrolet Silverado 2500 HD LT
2023 Chevrolet Silverado 2500 HD LTZ
2023 Chevrolet Silverado 2500 HD WT
2023 Chevrolet Silverado 3500 HD High Country
2023 Chevrolet Silverado 3500 HD LT
2023 Chevrolet Silverado 3500 HD LTZ
2023 Chevrolet Silverado 3500 HD WT
2023 GMC Sierra 2500 HD AT4
2023 GMC Sierra 2500 HD Denali
2023 GMC Sierra 2500 HD Pro
2023 GMC Sierra 2500 HD SLE
2023 GMC Sierra 2500 HD SLT
2023 GMC Sierra 3500 HD AT4
2023 GMC Sierra 3500 HD Denali
2023 GMC Sierra 3500 HD Pro
2023 GMC Sierra 3500 HD SLE
2023 GMC Sierra 3500 HD SLT
2024 Chevrolet Silverado 2500 HD Custom
2024 Chevrolet Silverado 2500 HD High Country
2024 Chevrolet Silverado 2500 HD LT
2024 Chevrolet Silverado 2500 HD LTZ
2024 Chevrolet Silverado 2500 HD WT
2024 Chevrolet Silverado 3500 HD High Country
2024 Chevrolet Silverado 3500 HD LT
2024 Chevrolet Silverado 3500 HD LTZ
2024 Chevrolet Silverado 3500 HD WT
2024 GMC Sierra 2500 HD AT4
2024 GMC Sierra 2500 HD Denali
2024 GMC Sierra 2500 HD Pro
2024 GMC Sierra 2500 HD SLE
2024 GMC Sierra 2500 HD SLT
2024 GMC Sierra 3500 HD AT4
2024 GMC Sierra 3500 HD Denali
2024 GMC Sierra 3500 HD Pro
2024 GMC Sierra 3500 HD SLE
2024 GMC Sierra 3500 HD SLT
2025 Chevrolet Silverado 2500 HD Custom
2025 Chevrolet Silverado 2500 HD High Country
2025 Chevrolet Silverado 2500 HD LT
2025 Chevrolet Silverado 2500 HD LTZ
2025 Chevrolet Silverado 2500 HD WT
2025 Chevrolet Silverado 3500 HD High Country
2025 Chevrolet Silverado 3500 HD LT
2025 Chevrolet Silverado 3500 HD LTZ
2025 Chevrolet Silverado 3500 HD WT
2025 GMC Sierra 2500 HD AT4
2025 GMC Sierra 2500 HD Denali
2025 GMC Sierra 2500 HD Pro
2025 GMC Sierra 2500 HD SLE
2025 GMC Sierra 2500 HD SLT
2025 GMC Sierra 3500 HD AT4
2025 GMC Sierra 3500 HD Denali
2025 GMC Sierra 3500 HD Pro
2025 GMC Sierra 3500 HD SLE
2025 GMC Sierra 3500 HD SLT
2026 Chevrolet Silverado 2500 HD Custom
2026 Chevrolet Silverado 2500 HD High Country
2026 Chevrolet Silverado 2500 HD LT
2026 Chevrolet Silverado 2500 HD LTZ
2026 Chevrolet Silverado 2500 HD WT
2026 Chevrolet Silverado 3500 HD High Country
2026 Chevrolet Silverado 3500 HD LT
2026 Chevrolet Silverado 3500 HD LTZ
2026 Chevrolet Silverado 3500 HD WT
2026 GMC Sierra 2500 HD AT4
2026 GMC Sierra 2500 HD Denali
2026 GMC Sierra 2500 HD Pro
2026 GMC Sierra 2500 HD SLE
2026 GMC Sierra 2500 HD SLT
2026 GMC Sierra 3500 HD AT4
2026 GMC Sierra 3500 HD Denali
2026 GMC Sierra 3500 HD Pro
2026 GMC Sierra 3500 HD SLE
2026 GMC Sierra 3500 HD SLT
Air Freight Prohibited: false
Not Carb Approved: false
Carb Acknowledgement Required: true
Ltl Freight Required: false
Prop 65: Y
Part Type: automotive
Epa: N/A
Units Per Sku: 1

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