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Exhaust› Exhaust Pipes, Systems and Components
Flowmaster
American Thunder Cat-Back Exhaust System Fits 2021-2025 Ford F-150 2.7L, 3.5L, 5.0L. American Thunder, Cat-Back, Dual Exit Stainless Steel Exhaust System Flowmaster
SKU: F00L 817979
Moderate — 2–4 hours
Overview
Show original supplier description
Part #: 817979
Flowmaster introduces our new American Thunder stainless steel cat-back exhaust system for the 2021-2025 Ford F-150 with the 2.7L, 3.5L and 5.0L engines. This system uses a Super 40 series muffler for a deep powerful sound and increased performance.Maximum dyno gains of 11 HP and 10 LB.FT. at the rear wheels. Mandrel bent 409 stainless steel tubing is used for maximum exhaust flow and durability. The system has a 3.0-inch inlet pipe and dual 2.5-inch tailpipes with both side exit and rear exit options that allow you to customize the look of the kit. 3.5-inch polished stainless steel tips finish off the kit for a classic performance look. All of the necessary hardware is included and factory-mounting locations are used for an easy installation. Backed by Flowmaster's Lifetime Limited Warranty.Includes Both Rear and Side Exit Tailpipes so the Final Look can be CustomizedSuper 40 Series Performance Muffler Delivers a Deep and Aggressive Performance ToneUses the Factory Hanger Locations for an Easy InstallationClears the Factory Spare TireStainless Steel Construction adds Durability3.50-Inch Polished Stainless Steel Tips add a Classic Performance LookDelta Flow Technology Increases Performance and Reduces DroneMandrel-bent Tubing Maximizes Exhaust FlowMaximum Dyno Gains of 11 HP and 10 LB.FT. at the Rear WheelsLifetime Limited Warranty
Features:
- Includes Both Rear And Side Exit Tailpipes So The Final Look Can Be Customized
- Includes Both Rear and Side Exit Tailpipes so the Final Look can be Customized
- Super 40 Series Performance Muffler Delivers A Deep And Aggressive Performance Tone
- Super 40 Series Performance Muffler Delivers a Deep and Aggressive Performance Tone
- Uses The Factory Hanger Locations For An Easy Installation
- Uses the Factory Hanger Locations for an Easy Installation
- Clears The Factory Spare Tire
- Clears the Factory Spare Tire
- Stainless Steel Construction Adds Durability
- Stainless Steel Construction adds Durability
- 3.50-Inch Polished Stainless Steel Tips Add A Classic Performance Look
- 3.50-Inch Polished Stainless Steel Tips add a Classic Performance Look
- Delta Flow Technology Increases Performance And Reduces Drone
- Delta Flow Technology Increases Performance and Reduces Drone
- Mandrel-bent Tubing Maximizes Exhaust Flow
- Mandrel-bent Tubing Maximizes Exhaust Flow
- Maximum Dyno Gains Of 11 Hp And 10 Lb.Ft. At The Rear Wheels
- Maximum Dyno Gains of 11 HP and 10 LB.FT. at the Rear Wheels
- Lifetime Limited Warranty
- Lifetime Limited Warranty
Exhaust System - American Thunder - Cat-Back - 3 in Diameter - Dual Rear / Side Exit - 3-1/2 in Polished Tips - Stainless - Natural - Ford Fullsize Truck 2021-22 - Kit
This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
Vehicle Symptoms
- Stock exhaust is too quiet and lacks character
- Want a deeper, more aggressive exhaust tone
- Looking for noticeable horsepower gains from exhaust upgrade
- Factory exhaust feels restrictive on acceleration
- Desire for a dual exhaust look with side exit option
Relevant Conversations
- Best exhaust system for 2021 F-150 5.0 for deep sound
- Flowmaster American Thunder vs Borla S-Type F-150
- How to install Flowmaster cat-back exhaust on 2021 F-150
- Does Flowmaster American Thunder increase horsepower?
- 2021 F-150 dual exhaust side exit kit
- Flowmaster Super 40 muffler sound clip F-150
- What cold air intake works with Flowmaster American Thunder?
- Upgrading exhaust on 2021 F-150 3.5 EcoBoost sound
- Flowmaster 817979 installation tips
- Will Flowmaster American Thunder void warranty?
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
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Specifications
| Brand | Flowmaster |
| Part Number | F00L 817979 |
Videos
2021-2024 5.0L F-150 Flowmaster American Thunder Dual Exhaust System Review & Sound Clip
21-25 F150 Flowmaster Outlaw Muffler Install
2021-2023 F-150 Flowmaster Outlaw Dual Exhaust System with Black Tips Review & Sound Clip
2021 Ford F-150 2 7T, 3.5T & 5.0L - Flowmaster Outlaw Exhaust - 817981
2015-2018 F150 Flowmaster American Thunder Dual Exhaust - Side/Rear Exit 5.0L Sound Clip & Install
2011-2014 F150 Flowmaster American Thunder Cat-Back Exhaust 5.0L Sound Clip & Install
Flowmaster American Thunder Exhaust 1999 5.4L F150
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Differences of the Outlaw, American Thunder, and Force II Exhaust Systems?
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