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Flowmaster

Flowmaster 18-23 Mustang 5.0L American Thunder Axle-Back Exhaust System (w/Valves)

Flowmaster 18-23 Mustang 5.0L American Thunder Axle-Back Exhaust System (w/Valves)

Regular price $ 1,899.95
Regular price $ 2,089.95 Sale price $ 1,899.95
Free shipping on orders over $99 (contiguous U.S.) — flat $10.99 under $99. Shipping details
Quantity
✓ In Stock Ships from manufacturer
Ships from Flowmaster — this item ships direct from the manufacturer. It usually goes out quickly, but because it leaves their warehouse rather than ours, delivery can take a little longer than our in-stock parts.

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.

  • For Vehicles With Active Performance Exhaust Option
  • Quad 4.00-inch Polished 304 Stainless Steel Tips
  • Aggressive Race-proven Outlaw Mufflers
  • Dyno Tuned for Maximum Performance
  • Uses the Factory Hanger Locations
  • Full Stainless Steel Construction
  • Straight-through Muffler Design
  • Lifetime Limited Warranty
  • Easy Installation

Vehicle Fitment

  • 2018-2023 Ford Mustang

Please verify exact fitment for your trim and engine before ordering.

🚚 Vendor Direct Shipment: This item is not stocked in our warehouse and ships directly from the manufacturer. Please allow additional handling time before dispatch.

Manufacturer Part Number: 817799

Images are for illustrative purposes only. Actual product may vary.

⚠ WARNING (California Proposition 65): This product can expose you to chemicals which are known to the State of California to cause cancer and/or birth defects or other reproductive harm. For more information go to www.p65warnings.ca.gov.

Manufacturer's Warranty — Flowmaster

Flowmaster warranty is tiered by material and product line. Lifetime Limited Warranty — stainless steel mufflers (FlowFX series excepted), all stainless steel exhaust systems (FlowFX included), stainless steel pipes, air intake kits and oiled-type filters (cleaning kits excepted), and other stainless steel exhaust accessories (exhaust tips and racing products excepted); this runs for the life of the original vehicle the part was installed on. Three (3) years — aluminized steel mufflers, exhaust systems and pipes, all exhaust tips, other non-race exhaust accessories, and commercial-vehicle applications of aluminized or stainless products. Two (2) years — Delta Force dry air intake filter elements. One (1) year — FlowFX series mufflers, Elite Series headers, and electronic components such as Delta Boost modules. Catalytic converters sold under the Flowmaster brand are excluded from this warranty. Coverage runs from the date of original purchase, to the original purchaser only, and only while the part remains on the vehicle it was originally installed on. Header coverage does not extend to damage caused by exhaust insulating wrap and is void if the header was fitted to a new or rebuilt engine during the initial break-in period. Sound-absorbing material inside “straight-through” mufflers degrades over time; Flowmaster treats that as normal wear, not a material defect. Also excluded: interior and exterior sound levels, cosmetic issues such as coatings and material discoloration, installation on a racing vehicle, improper installation or installation contrary to Flowmaster instructions, alteration, misuse, repair, accident, collision, undercarriage road impact or debris, and willful or negligent acts. To claim, the original purchaser returns the product either to the original retailer or directly to Flowmaster — a Returned Material Authorization (RMA) number must be obtained from Flowmaster first if returning to them — with proof of purchase showing place, price, product and date. Flowmaster's remedy is exchange for the same part number or refund of the purchase price at its option; installation, labor, towing and shipping costs are not covered.

Warranty terms are set by the manufacturer and may change. Full details and claims are handled directly by Flowmaster. Contact us if you need help with a warranty claim.

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