Flowmaster · New
Flowmaster 18-23 Mustang 5.0L American Thunder Axle-Back Exhaust System (w/Valves)
MPN 817799 · Store SKU flo817799
Supplier stock checked 11/8/2026, 3:26:27 AM UTC. Adding a part does not reserve it.
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Product details
This Flowmaster® American Thunder® Axle-back exhaust system is for 2018-2023 Ford Mustang GT coupes and convertibles with the 5.0L engine and Factory Active Performance Exhaust Option. System features include a pair of specially designed Outlaw® series mufflers giving you high flow with a moderately aggressive exterior and interior tone when the valves are closed, and an aggressive "wide open" exterior sound level when you open up the valves. Other features include large 3.00-inch mandrel-bent 409S stainless steel tubing for high flow, durability, and longevity. Add to that, a pair of our high-quality valves to accommodate the factory exhaust actuators for when you really want to open up the sound. The system is finished off with quad 4.00-inch polished 304 stainless steel tips for an aggressive look that demands attention, the same as the exhaust note. Includes all necessary parts, hardware and detailed instructions for an easy installation you can do at home. Covered by our Lifetime Limited Warranty. Note: Fits both coupes and convertibles. Fits 2018-2023 Mustang GT 5.0L with Factory Active Performance Exhaust Valves. - Aggressive to moderate sound Flowmaster American Thunder Axle-back Exhaust System
Manufacturer fitment & guides
Check 817799 against the manufacturer’s application information below.
Part-specific notes
- California Proposition 65: Y
