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2018 - 2022 Mustang GT MRT Street Race Axle Back
MRT 304 Stainless Axle-back: 2018+ Mustang GT #91U921
MRT Part# 91U921
Loudness: 8 Drone: 2 Performance: 6
2018 thru 2021 Mustang GT.
: None Required
Time to Install:
Retail Price: $791.98
Price with Options:
Usually Ships in 1 to 2 Business Days
Polished T304 SS Tips - Standard
Black Ops - Quad Tip Blackout [Add $300.00]
The Mustang GT MRT Street Race Axle Back system has a loud, deep muscle car sound and is handcrafted in corrosion resistant T304 Stainless Steel. Base systems include T304 polished SS 4" tips and 2.5" mandrel bent tube. Black Ops black matte tip finish is available for an additional fee. This system is engineered for the best sound to match your GT and provides increased performance from increased exhaust flow. The MRT
Street Race Axle Back is l
ouder than the Sport Touring Exhaust
This Badass series has just enough exhaust presence with elevated sound to Get Noticed, Feel the Performance note and packaged in a design without excessive drone.
For customers with factory-installed Active & Dual Mode Exhaust valves, MRT offers and recommends a simple solution that allows you to upgrade your exhaust system without having to develop a tune. For more information on these plates, refer to
MRT Part #92G155
or simply add to your shopping cart before checkout.
2018 thru 2021
Mustang GT Coupe and convertible
Hear the Difference
How does it sound? The MRT Mustang GT Street Race Axle Back #91U921 has a balanced, deep muscle car sound.
Is there drone or resonance? The drone is noticeable but tolerable.
What if I step on it? Wide-open throttle increases exhaust loudness for an aggressive performance sound.
Are you located close to Plymouth, MI and need your MRT aftermarket exhaust installed? Call MRT at 734-455-5807 to make an appointment today!
Handcrafted by MRT
What kind of steel is it made from? Corrosion-resistant T304 stainless steel.
Where is it made? Developed and handcrafted in-house at MRT facility in Plymouth, Michigan, USA.
How long is the Warranty?
Limited Lifetime Warranty
(See Warranty Page for Details)
Feel the Performance
What is the muffler design? Straight through design to provide maximum exhaust gas flow.
What is the tube diameter? A large 2.5" tube is used for reduced exhaust flow restrictions.
What are the performance gains? Reducing restriction and maximizing flow provides for noticeable gains.
What kind of tip is it? Dual 4" double wall, polished T304 stainless steel tips with beveled edges. .
What are my tip finish options? Stylish Polished Stainless Steel or Black Ops Matte Ceramic.
How do I get noticed? Great sound and great looks turn heads and get positive comments!
Can I install this myself? Yes, MRT engineers this Premium Exhaust System for a simple do-it-yourself (DIY) installation.
How long does it take to install? Installation time is about 1 hour and requires only common hand tools.
What is included? All necessary hardware included.
DIY installation for the backyard mechanic
T304 Stainless Steel for the best corrosion resistance
Engineered, designed and manufactured in the USA
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