Flowmaster
Flowmaster 18-23 Mustang 5.0L American Thunder Axle-Back Exhaust System (w/Valves)
Why this price?
$1,899.95 is MSRP, the lowest price Flowmaster lets us list it at. Additionally, Pro members get $208.99 back on this part.
$1,899.95 − $208.99 = $1,690.96
Special Order
This part is still available to order. Once you place your order, we’ll submit it directly to Flowmaster, and they’ll ship it straight to you.
Delivery times can vary depending on the brand, so we can’t guarantee an exact arrival date. What we can guarantee is that we’ll stay on top of your order, monitor its progress, and keep you updated until it reaches your door.
Special-order items are typically not kept in stock by most retailers. By ordering through us, your order is placed directly with Flowmaster, assuring you get the part as quickly as possible.
Want to get an estimated delivery timeframe before ordering? Contact us through our contact page, and we’ll be happy to find out for you.
Not sure it fits? Read our tips.
Fitment tips
Fitment can come down to more than year, make and model. Sometimes the sub-model decides, so start with the fitment table below.
- Drive type. If your car is all-wheel drive, make sure the part is for all-wheel drive, not rear-wheel drive.
- Engine size. For engine parts, make sure the engine size on the product matches your engine.
- Transmission. Manual and automatic cars often take different parts.
- Body style. Sedan or hatch, two-door or four-door, cab and bed length on trucks.
Manufacturer data can sometimes have imperfections. Still not sure? We are happy to help.
Send us a message and we will confirm the fit.
Couldn't load pickup availability
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.
Installation InstructionsWarranty
- 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
This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2019-2020 | Ford | Mustang | Bullitt |
| 2018-2023 | Ford | Mustang | GT |
| 2018-2023 | Ford | Mustang | GT Premium |
| 2021-2023 | Ford | Mustang | Mach 1 |
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