(approx) 1 Hour
Light to Moderate mechanical skill required.
The Flowmaster Outlaw Series axle-back exhaust is for the 2015 and newer EcoBoost Mustang owners out there that are looking for an axle-back that'll be more refined and deeper sounding and is made from stainless steel with one of the most budget-friendly price points. So Exhaust for the S550 can get expensive fast, even axle-backs, but this is one of the more affordable options that still offers stainless steel materials. The install for this is easy. It should take you about an hour to complete and it's a two out of three wrenches on the difficulty meter since there is some cutting involved, but, of course, I'll get more into that later. One of the more important things when it comes to shopping for exhaust is going to be the sound. Like I said, consider this as one of the more refined sounding axle-backs for an EcoBoost. It gives more volume and more sound for sure and it's deeper than the stock exhaust, but it steers away from being obnoxious. A lot of times when systems provide a ton of volume increase for the EcoBoost, that's when you really start to get into the import sounding exhaust. If you're looking to steer away from that, this is one of the ones that you're gonna want to consider. Of course the EcoBoost is a four-cylinder turbo car, so that's what it's gonna sound like ultimately. I would call this system a three out of five on the loudness scale, with one being a quiet upgrade and five being a very loud upgrade. You do get more turbo noise with this axle-back since you are opening up exhaust flow around that turbo, and there is an occasional crackle on decel. Still, you don't have to worry about any drone in the interior with this axle-back. You're looking at two and half-inch mandrel bent tubing with this axle-back, which means that Flowmaster did step up the diameter here. The stock exhaust had a two and a quarter-inch diameter. This is made from 16-gauge 409 stainless steel tubing which is gonna be nice for those of you out there that are looking for an exhaust that'll have corrosion resistance and a longer life. Stainless steel will always last longer than aluminized steel would and will hold up better against corrosion. This system finishes with four-inch polished stainless steel tips. Price-wise, this is one of the more affordable options if you look at everything that is currently available. You can expect to pay a little over $400 for this axle-back, which is a good price considering the materials that you have here. Axle-backs for the EcoBoost range anywhere from just over $400 to nearly $1700. And as always if this one doesn't have the sound that you're looking for you have a ton of other options to check out. You're gonna be looking at the typical cut and clamp design with the install for this axle-back since you do need to cut all S550 axle-backs. I'm gonna call this a two out of three wrenches on the difficulty meter but just because of the cutting that's involved. It's nothing too difficult, but I just recommend some eye protection and a fresh Sawzall blade to make things easier. Overall, you're looking at about two hours to get this all done. A lift would certainly make things easier for you here, but the job can be done on jack stands as well if you don't happen to have access to one. Cutting the factory axle-back isn't hard. Just be sure to measure twice and plan and mark where you're gonna be cutting the factory axle-back so you don't make a mistake. You can always mark the axle-back with painters tape if you want to, then use the Sawzall to cut the stock axle-back out. It'll probably be easiest to leave the hangers on the axle-back and just unbolt them from the car. You can transfer them over to the new axle-back then. The new axle-back will come with new clamps for you, so you don't have to worry about that. When you go to install your new setup, it'll probably be easiest to leave everything loose until you have it all lined up and then tighten it down. This is the Flowmaster Outlaw axle-back exhaust for the 2015 and newer EcoBoost Mustang, and you can check it out more online right here at americanmuscle.com.
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Features, Description, Reviews, Q&A, Specs & Installation
Fitment: 2015 2016 2017 Details
CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
April 06, 2020
yep loves these pipes but sometimes i wish i had a v8Helpful (0)
April 05, 2020
First mod on my car Love driving with that super sound. AwesumHelpful (0)
April 04, 2020
Good quality sound, not loud but not soft. Just perfectHelpful (0)
March 31, 2020
Awesome value for what you get, super easy to install and great sound for one of the cheaper available kits. Really brought my v6 to life. No drone in the car either once you get to cruising speed.Helpful (0)
March 30, 2020
A nice roar for a Eco
This made my 2017 Ecoboost sound pretty darn aggressive, I love it. Not too loud but also not too quiet!Helpful (0)
March 02, 2020
was a little hesitant purchasing in the beginning just because i looked up videos of this exhaust and i wasn’t too thrilled with how it sounded.. but after i got it installed it sounds great and i’m super happy with it!! on a cold start you can really tell a difference. highly recommend!Helpful (1)
January 27, 2020
FLOWMASTER OUTLAWS V6
Sounds great on cold start. Quiet when your not on the gas. Sounds good at low rpm and higher rpms. Around 2k rpms sounds like a honda at least from inside the car. Drone is extreme in that 2k range as well. Hopefully H pipe will help.Helpful (2)
January 21, 2020
Awesome exhaust system
It is a good sounding exhaust for EcoBoost. The sound is awesome doesn’t sound like a lawnmower and looks super aggressive. Pretty easy install as well.Helpful (0)
January 10, 2020
Amazing Exhaust Sound
The Outlaws are undefeated!!! The exhaust is very aggressive and has a nice rumble at idle. It is not raspy at all. If you like drone then these are for you because it's plenty of it.Helpful (0)
November 26, 2019
A little loud
Love the sound but is a little louder than I originally expected.Helpful (1)
Does installing the Flowmaster Outlaw Series Axle-Back Exhaust on my 2017 Mustang eccoboost affect the new vehicle warranty from FORD?
Hello, Ford explained to me that the only way and after market part would void the warranty is it poorly malfunctioning.
I have the convertible version of the 2015 Mustang Ecoboost Premium. With this axle-back fit?
The Flowmaster Outlaw Series Axle-Back Exhaust is designed to fit both coupe and convertible ecoboost Mustangs.
is this product legal in the Rio Grande Valley ,Texas
Unfortunately, we are not familiar with the local laws and regulations in your city. Please contact your local Department of Transportation, and/or Law Enforcement Agency.
I live in California. If i put this on, will i still pass smog? This is probably the only reason holding me back. I have a 2017 v6 mustang.
The Flowmaster axle backs will pass smog testing however you will want to check your local laws on noise restraints to be safe.
Is this system compatible with the Flowmaster Scavenger series Y-pipe?
The Flowmaster Scavenger Series Cut and Clamp Resonator Delete Y-Pipe, Item 389694 is compatible with these axle-backs. http://www.americanmuscle.com/flowmaster-y-pipe-2015gt.html
These Flowmaster Outlaw Series Axle-Back Exhaust include the muffler assemblies and the clamps shown in the product photos.
A tune is not required for this axle-back, though it would be a good idea to get one. Since this axle-back is changing the air flow, a custom tune will help give you the most power.
Hello! Yes, the installation of this Axle-Back Exhaust requires cutting and removing the stock muffler assemblies, and clamping the new muffler assemblies in place. Because this exhaust starts where there is no section to unbolt you will have to cut and slip it into the existing piping coming out of the muffler.
The Flowmaster Outlaw Series Axle-Back Exhaust is CARB legal since it does not affect the catalytic converters. The only issue you could face is that this exhaust is one of the louder ones. Research your local noise ordinances to make sure the sound level of this exhaust would be legal in your area.
This will not fit EcoBoost models.
Unfortunately we do not have the exact dB, but the outlaws are one of the loudest exhausts available. There may be some drone near the 2000 RPM range.
Yes, the axle-backs will generally pass emissions without any issues. Please know it can depend on the state and their emission laws. We recommend checking with the state ordinances or a local shop.
This should not cause the throttle to be less responsive. We would recommend checking with a shop to confirm what the issue may be.
You will need to reach out to Flowmaster directly for this.
(approx) 1 Hour
Light to Moderate mechanical skill required.
What's in the Box
|Piping Material:||409 Stainless Steel||Tip Material :||Polished Stainless Steel|
|Piping Size:||2.5"||Tip Size:||4.0"|
|Muffler Type:||Straight-through||Fitment:||2015-2017 V6|