18-23 Ford Mustang GT 5.0L V8 Flowmaster 817799 American Thunder Axle-back Exhaust System

Flowmaster American Thunder Axle-Back Exhaust System for 2018-2023 Ford Mustang GT 5.0L with Active Exhaust

Part Number: 817799

Transform the sound and appearance of the 2018-2023 Ford Mustang GT 5.0L with the Flowmaster American Thunder Axle-Back Exhaust System. Engineered specifically for Mustang GT coupes and convertibles equipped with the factory Active Performance Exhaust, this premium axle-back system delivers the best of both worlds. With the exhaust valves closed, the race-proven Outlaw® mufflers produce a refined yet moderately aggressive tone for comfortable cruising. Open the factory valves and the system unleashes an aggressive, wide-open exhaust note worthy of the Mustang's legendary V8 performance. Constructed from durable stainless steel with large mandrel-bent tubing and finished with quad polished 304 stainless steel tips, this system enhances exhaust flow, improves durability, and gives the rear of the vehicle an unmistakable performance appearance. Designed to reuse the factory exhaust actuators and mounting locations, this high-quality Flowmaster system offers an exceptional combination of performance, sound, fitment, and long-lasting value.

Key Features

• Designed for 2018-2023 Ford Mustang GT 5.0L models equipped with Factory Active Performance Exhaust.
• Premium American Thunder axle-back exhaust system.
• Race-proven Outlaw® mufflers provide moderate sound with valves closed and aggressive sound when opened.
• Large 3.00-inch mandrel-bent 409 stainless steel tubing promotes improved exhaust flow.
• OEM-style exhaust valves included for compatibility with factory active exhaust actuators.
• Quad 4.00-inch polished double-wall 304 stainless steel exhaust tips with embossed Flowmaster logo.
• Straight-through performance muffler design.
• Uses factory hanger locations for a precise fit.
• Includes clamps, hardware, and installation instructions.
• Manufactured from corrosion-resistant stainless steel for long service life.

Benefits

• Produces an aggressive muscle car exhaust tone while retaining factory active exhaust functionality.
• Improves exhaust flow for enhanced overall performance characteristics.
• Maintains comfortable cruising with valves closed while delivering an exhilarating exhaust note on demand.
• Adds an aggressive rear appearance with polished quad stainless steel tips.
• Direct-fit design minimizes installation time and eliminates unnecessary modifications.
• Built from premium stainless steel materials for exceptional durability and corrosion resistance.
• Backed by Flowmaster's Lifetime Limited Warranty for long-term peace of mind.

Product Specifications

• Brand: Flowmaster
• Part Number: 817799
• Product Type: Axle-Back Exhaust System
• Exhaust Series: American Thunder
• Sound Level: Aggressive / Moderate
• Vehicle Compatibility: Factory Active Performance Exhaust equipped vehicles only
• Main Pipe Diameter: 3.00 inches
• Pipe Material: 409 Stainless Steel
• Pipe Finish: Natural
• Muffler Material: 409 Stainless Steel
• Muffler Finish: Black High-Temperature Paint
• Muffler Shape: Oval
• Muffler Quantity: 2
• Valve Type: OEM-Style Valves
• Valve Actuators: Reuses factory OEM actuators
• Exhaust Tip Material: 304 Stainless Steel
• Exhaust Tip Finish: Polished
• Exhaust Tip Color: Silver
• Exhaust Tip Diameter: 4.00 inches
• Exhaust Tip Length: 5.25 inches
• Exhaust Tip Style: Double-Wall Round Angle Cut
• Exhaust Tip Quantity: 4
• Exit Style: Dual Rear Exit
• Inlet Connection: Slip-Fit Clamp-On
• Clamps Included: Yes
• Hangers Included: Yes
• Catalytic Converters Included: No
• California Proposition 65: Yes

Install Difficulty Level

Easy. This direct-fit axle-back system is designed to utilize the factory hanger locations and reuse the OEM active exhaust actuators. All required clamps, hardware, and detailed instructions are included. Basic hand tools and cutting of the factory exhaust are required. Installation can be completed in approximately 1 hour by an experienced DIY enthusiast or professional installer.

Vehicle Fitment

• 2018 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2018 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust
• 2019 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2019 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust
• 2020 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2020 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust
• 2021 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2021 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust
• 2022 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2022 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust
• 2023 Ford Mustang GT Coupe 5.0L V8 with Factory Active Performance Exhaust
• 2023 Ford Mustang GT Convertible 5.0L V8 with Factory Active Performance Exhaust

If there are any questions about this product or if a product description inaccuracy needs to be reported, please contact the MPT Performance experts at (407) 636-7077 or by email for assistance.