Flowmaster · New
Flowmaster 99-04 Mustang GT 4.6L American Thunder SS Cat-Back Exhaust System
MPN 817312 · Store SKU flo817312
Supplier stock checked 11/8/2026, 7:27:17 AM UTC. Adding a part does not reserve it.
Request a return within 30 calendar days after delivery. New parts must be unopened and unused.
Shipping & returns ↗This policy does not limit rights required by law.Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.
Product details
For the person who is looking for a complete Flowmaster® cat-back dual exhaust system with an aggressive tone. With easy fit in mind, this American Thunder® exhaust system features mandrel-bent 2.50-inch stainless steel tubing for maximum performance and includes a pair of specially selected Super 40® Series performance mufflers. The custom tailpipes feature added clearance and exit in the factory location with large 3.00-inch polished tips. The system uses the factory hanger locations for an easy install and delivers a moderate to aggressive interior and exterior tone, best suited to the enthusiast who wants their performance to be heard. Like all Flowmaster systems, the benefits include improved throttle response, power and mileage and are designed for an easy fit. The system includes all necessary parts, hardware and instructions for an easy installation you can do at home. 1999-2004 Ford Mustang GT, MACH1 and Bullitt with 4.6L SOHC engine, Stainless Steel - Aggressive to moderate sound Flowmaster American Thunder Cat-back Exhaust System
Manufacturer fitment & guides
Check 817312 against the manufacturer’s application information below.
A manufacturer application guide is not available for this listing. Request the exact application from JuiceBuilt before payment.
Part-specific notes
- Emissions acknowledgement required before purchase.
- California Proposition 65: Y
