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Flowmaster Flowmaster Flow FX Direct Fit Muffler 718155
$449.95
$435.99
Flowmaster's® FlowFX Direct-Fit Muffler exhaust system for the 2020-2025 GM 2500HD and 3500HD trucks with the 6.6L gas engines gives you a great value packed way to help you customize your GM truck to your personality. This performance muffler 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 409 stainless steel Flow FX series "straight-through" muffler for great sound and maximum performance and no drone. The muffler then connects to the factory tailpipe for a simple and effective performance upgrade. Max dyno gains of 7 hp and 5 lb-ft at the rear wheels. This results in better acceleration and towing performance. The system uses all the factory hanger locations and connections for an easy installation that you can do at home. Kits include installation instructions and all necessary hardware. Backed by Flowmaster's Lifetime Limited Warranty.
This Part Fits:
| Year | Make | Model | Submodel | Notes |
|---|---|---|---|---|
| 2020 | Chevrolet | Silverado 2500 HD | Custom | |
| 2021 | Chevrolet | Silverado 2500 HD | Custom | |
| 2022 | Chevrolet | Silverado 2500 HD | Custom | |
| 2023 | Chevrolet | Silverado 2500 HD | Custom | |
| 2024 | Chevrolet | Silverado 2500 HD | Custom | |
| 2025 | Chevrolet | Silverado 2500 HD | Custom | |
| 2020 | Chevrolet | Silverado 2500 HD | High Country | |
| 2021 | Chevrolet | Silverado 2500 HD | High Country | |
| 2022 | Chevrolet | Silverado 2500 HD | High Country | |
| 2023 | Chevrolet | Silverado 2500 HD | High Country | |
| 2024 | Chevrolet | Silverado 2500 HD | High Country | |
| 2025 | Chevrolet | Silverado 2500 HD | High Country | |
| 2020 | Chevrolet | Silverado 2500 HD | LT | |
| 2021 | Chevrolet | Silverado 2500 HD | LT | |
| 2022 | Chevrolet | Silverado 2500 HD | LT | |
| 2023 | Chevrolet | Silverado 2500 HD | LT | |
| 2024 | Chevrolet | Silverado 2500 HD | LT | |
| 2025 | Chevrolet | Silverado 2500 HD | LT | |
| 2020 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2021 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2022 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2023 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2024 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2025 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2020 | Chevrolet | Silverado 2500 HD | WT | |
| 2021 | Chevrolet | Silverado 2500 HD | WT | |
| 2022 | Chevrolet | Silverado 2500 HD | WT | |
| 2023 | Chevrolet | Silverado 2500 HD | WT | |
| 2024 | Chevrolet | Silverado 2500 HD | WT | |
| 2025 | Chevrolet | Silverado 2500 HD | WT | |
| 2020 | Chevrolet | Silverado 3500 HD | High Country | |
| 2021 | Chevrolet | Silverado 3500 HD | High Country | |
| 2022 | Chevrolet | Silverado 3500 HD | High Country | |
| 2023 | Chevrolet | Silverado 3500 HD | High Country | |
| 2024 | Chevrolet | Silverado 3500 HD | High Country | |
| 2025 | Chevrolet | Silverado 3500 HD | High Country | |
| 2026 | Chevrolet | Silverado 3500 HD | High Country | |
| 2020 | Chevrolet | Silverado 3500 HD | LT | |
| 2021 | Chevrolet | Silverado 3500 HD | LT | |
| 2022 | Chevrolet | Silverado 3500 HD | LT | |
| 2023 | Chevrolet | Silverado 3500 HD | LT | |
| 2024 | Chevrolet | Silverado 3500 HD | LT | |
| 2025 | Chevrolet | Silverado 3500 HD | LT | |
| 2026 | Chevrolet | Silverado 3500 HD | LT | |
| 2020 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2021 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2022 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2023 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2024 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2025 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2026 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2020 | Chevrolet | Silverado 3500 HD | WT | |
| 2021 | Chevrolet | Silverado 3500 HD | WT | |
| 2022 | Chevrolet | Silverado 3500 HD | WT | |
| 2023 | Chevrolet | Silverado 3500 HD | WT | |
| 2024 | Chevrolet | Silverado 3500 HD | WT | |
| 2025 | Chevrolet | Silverado 3500 HD | WT | |
| 2026 | Chevrolet | Silverado 3500 HD | WT | |
| 2020 | GMC | Sierra 2500 HD | AT4 | |
| 2021 | GMC | Sierra 2500 HD | AT4 | |
| 2022 | GMC | Sierra 2500 HD | AT4 | |
| 2023 | GMC | Sierra 2500 HD | AT4 | |
| 2024 | GMC | Sierra 2500 HD | AT4 | |
| 2025 | GMC | Sierra 2500 HD | AT4 | |
| 2020 | GMC | Sierra 2500 HD | Denali | |
| 2021 | GMC | Sierra 2500 HD | Denali | |
| 2022 | GMC | Sierra 2500 HD | Denali | |
| 2023 | GMC | Sierra 2500 HD | Denali | |
| 2024 | GMC | Sierra 2500 HD | Denali | |
| 2025 | GMC | Sierra 2500 HD | Denali | |
| 2020 | GMC | Sierra 2500 HD | SLE | |
| 2021 | GMC | Sierra 2500 HD | SLE | |
| 2022 | GMC | Sierra 2500 HD | SLE | |
| 2023 | GMC | Sierra 2500 HD | SLE | |
| 2024 | GMC | Sierra 2500 HD | SLE | |
| 2025 | GMC | Sierra 2500 HD | SLE | |
| 2020 | GMC | Sierra 2500 HD | SLT | |
| 2021 | GMC | Sierra 2500 HD | SLT | |
| 2022 | GMC | Sierra 2500 HD | SLT | |
| 2023 | GMC | Sierra 2500 HD | SLT | |
| 2024 | GMC | Sierra 2500 HD | SLT | |
| 2025 | GMC | Sierra 2500 HD | SLT | |
| 2020 | GMC | Sierra 3500 HD | AT4 | |
| 2021 | GMC | Sierra 3500 HD | AT4 | |
| 2022 | GMC | Sierra 3500 HD | AT4 | |
| 2023 | GMC | Sierra 3500 HD | AT4 | |
| 2024 | GMC | Sierra 3500 HD | AT4 | |
| 2025 | GMC | Sierra 3500 HD | AT4 | |
| 2020 | GMC | Sierra 3500 HD | Denali | |
| 2021 | GMC | Sierra 3500 HD | Denali | |
| 2022 | GMC | Sierra 3500 HD | Denali | |
| 2023 | GMC | Sierra 3500 HD | Denali | |
| 2024 | GMC | Sierra 3500 HD | Denali | |
| 2025 | GMC | Sierra 3500 HD | Denali | |
| 2020 | GMC | Sierra 3500 HD | SLE | |
| 2021 | GMC | Sierra 3500 HD | SLE | |
| 2022 | GMC | Sierra 3500 HD | SLE | |
| 2023 | GMC | Sierra 3500 HD | SLE | |
| 2024 | GMC | Sierra 3500 HD | SLE | |
| 2025 | GMC | Sierra 3500 HD | SLE | |
| 2020 | GMC | Sierra 3500 HD | SLT | |
| 2021 | GMC | Sierra 3500 HD | SLT | |
| 2022 | GMC | Sierra 3500 HD | SLT | |
| 2023 | GMC | Sierra 3500 HD | SLT | |
| 2024 | GMC | Sierra 3500 HD | SLT | |
| 2025 | GMC | Sierra 3500 HD | SLT |
Specifications:
| 52 | 5 |
| 614 | 5 |
| Body Length | 18 |
| Body Material | 409 Stainless Steel |
| 616 | 8 |
| Brand | Flowmaster |
| California Proposition 65 | Yes |
| California Proposition 65 Chemical Name | Nickel (Metallic) |
| California Proposition 65 Chemical Name | Chromium (hexavalent compounds) |
| California Proposition 65 Required | Yes |
| Catalytic Converter Included | No |
| Category | Exhaust |
| Clamping Type | Flat Band |
| Clamps Included | Yes |
| Color | Natural |
| Emission Code | 5 |
| Exhaust Series | FlowFX |
| Exhaust Tip Quantity | 0 |
| Exit Position | OEM |
| 200 | Natural |
| 353 | No |
| 3390 | Performance |
| Heat Shield | No |
| 618 | No |
| Inlet Diameter | 3.5 |
| 601 | 3.52 |
| 619 | Center |
| 1171 | 3.11 |
| 620 | 1 |
| 596 | Slip-Fit |
| Main Piping Diameter | Center |
| Material | 409 Stainless Steel |
| Mount Type | Uses Factory Hangers |
| Muffler Body Length | 10 |
| Muffler Body Length (in) | 10 |
| Muffler Body Material | 409 Stainless Steel |
| Muffler Body Shape | Round |
| Muffler Body Width | 8 |
| Muffler Color | Natural |
| Muffler Finish | Natural |
| Muffler Inlet Location | Center |
| 630 | 409 Stainless Steel |
| Muffler Outlet Location | Center |
| Muffler Part Number | Kit Only |
| Muffler Quantity | 1 |
| Muffler Series | FlowFX |
| 631 | Oval |
| 1174 | Absorption |
| Outlet Diameter | 3.5 |
| 622 | 3.52 |
| 304 | Center |
| 1172 | 3.65 |
| 623 | 1 |
| 598 | Slip-Fit |
| 8971 | 34.25 |
| part type | Exhaust Muffler Assembly |
| Pipe Material | 409 Stainless Steel |
| Product Type | Exhaust System |
| Shape | Oval |
| Single Dual | Single |
| Sound Level | Aggressive / Moderate |
| Sub Category | Mufflers |
| System Type | Direct-fit Muffler |
| Tubing Diameter | 3.5 |
| Tubing Diameter (in) | 3.5 |
| Tubing Material | 409 Stainless Steel |
| Type | Direct-fit Muffler |
| Type of Muffler | Absorption |
| Valve Actuator Included | No |
| Valve Included | No |
| Valve Type | Not Applicable |
| Vehicle Type | Truck/SUV |
| Warning | California Proposition 65 |
| Description_INV | 20-25 GM 2500/3500 6.6L GAS DIR FIT FFX |
| Description_DES | Flowmaster Flow FX Direct Fit Muffler |
| Description_EXT | Fits 20-25 GM 2500HD/3500HD 6.6L Gas Engine FFX Direct Fit Muffler Exhaust System, 409 stainless steel |
| Description_MKT | Flowmaster's® FlowFX Direct-Fit Muffler exhaust system for the 2020-2025 GM 2500HD and 3500HD trucks with the 6.6L gas engines gives you a great value packed way to help you customize your GM truck to your personality. This performance muffler 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 409 stainless steel Flow FX series "straight-through" muffler for great sound and maximum performance and no drone. The muffler then connects to the factory tailpipe for a simple and effective performance upgrade. Max dyno gains of 7 hp and 5 lb-ft at the rear wheels. This results in better acceleration and towing performance. The system uses all the factory hanger locations and connections for an easy installation that you can do at home. Kits include installation instructions and all necessary hardware. Backed by Flowmaster's Lifetime Limited Warranty. |
| Description_FAB | 3.5-inch mandrel bent 16-gauge 409 stainless steel tubing maximizes exhaust flow and improves durability |
| Description_FAB | Kit includes complete hardware and factory styled hangers in the stock locations for an easy installation |
| Description_FAB | A tuned Flow FX style muffler delivers a deep, aggressive to moderate performance tone and improves exhaust flow with no drone |
| Description_FAB | Max increases of up to 7 hp and 5 lb-ft over the stock exhaust at the wheels |
| Description_FAB | Tuned performance muffler eliminates interior drone |
| Description_FAB | Maintains factory warranty |
| Description_FAB | Lifetime Limited Warranty |