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Stainless Works 3-Inch Retro LMF Cat-Back Exhaust with X-Pipe (15-17 GT Fastback)

Item 393692
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      Review & Installation Video

      What's up, guys? I'm Justin with, and this my detailed review and install of the Stainless Works Retro Three-inch LMF Cat-back exhaust system, available for your 2015 and up Fast-back GT with X-pipe. I'm gonna be covering a lot of ground in this video, guys, so bear with me. We're gonna talk about what kind of sound you can expect when using the X-pipe version of the LMF system from Stainless Works, what's you're gonna be looking at as far as basic materials and construction, and then finally a quick little walk-through of the install here, guys.And honestly, no cutting, no permanent modification, a real simple one out of three wrenches on the difficulty meter, with a little bit more detail coming up later on. All right, guys, so you should be checking out the LMF Cat-back from Stainless Works here if you're after one of the most aggressive and one of the most loud systems available in the after-market, thanks to the X-pipe design, and one that's gonna use some of the best materials possible. On top of that, you should be looking at this thing if you're after all the stuff I just said, and you'd like to get all of that for around a $1,000 price-point. So with all that said, guys, let's take a closer look here at the Stainless Works. So the LMF came to life basically as a response to the people who really enjoyed the sound of the original retro-chambered cat-back from Stainless Works, the two-and-a-half inch version, but wanted something that was gonna be a little bit more loud, and something that was gonna offer three-inch cores or mufflers for the higher horsepower applications. The result is the LMF here, again from Stainless Works, and if you heard the sound clips at the top of this video you probably have a good idea what LMF stands for. And, as advertised, this system is one loud MF as you heard with the sound clips here. An easy five out of five on my one to five, or one to wake the neighbors scale. And believe me when I tell you here, guys, this is one of those systems where you're just gonna have to take my word for it, it's a lot louder than you're getting through your headphones or your computer speakers. You're also picking up a good amount of rasp with this system, but it's really no surprise when you're looking at such a free-flowing system like this, and one that does incorporate the X-pipe. And for all that sound you're getting on the outside, you're also picking up a good amount of sound on the inside as well. But it really isn't unbearable. In fact, it tends to go with the Mustang, and just adds to the experience, in my opinion. So how does this system get its name? Well, again, Stainless Works took their extremely popular two-and-a-half-inch retro-chambered system and just gave it a little more size, and giving it a lot more sound in the process. The standard retro-chambered system, again two-and-a-half-inch cores or mufflers, the retro-chambered LMF gets bumped up to a full three-inch muffler and resonator, increasing the performance a little bit, but really cranking up the sound in the process. The actual sound is shaped by the retro-chambered three-inch mufflers and resonators, working in conjunction with that included X-pipe of course, giving you that slightly higher-pitched tone, maybe a little bit more rasp as well. It is worth mentioning here, gang, that this thing is available, but with an H-pipe in place of that X-pipe. So if you wanted a slightly deeper tone overall, maybe a little less volume, you should definitely check that out. In fact, cruise on over to the product page, listen to the sound clips, and you can hear what this thing's all about. I do want to quickly go back to the larger core or muffler here, just real quick, and reiterate that this would be an awesome choice for those boosted S550 GTs out there, or maybe the guys planning on going forced induction down the road. That's just because the boosted GTs love a slightly larger diameter system overall, and this thing really fits the bill there. And while on topic of configuration, let's talk about the connection here real quick. As you can see, this guy does feature the factory style connection with this particular system. However, if you wanted to eliminate that neck-down, get rid of that choke-point altogether, Stainless Works does offer a full three-inch system from tip to tip, eliminating the factory style connection here. But you have to use this system with a set of Stainless Works long-tube headers, and you can check that out here at AM as well, if you want.All right, guys. Let's switch gears, real quick, let's talk construction for a little bit. And again, nothing but the best from Stainless Works here. Premium 304 grade stainless-steel throughout, including the three-inch mandrel-bent tubing, the retro-chambered mufflers and resonators, and finally the four-inch conical wall tips. Now, premium stainless-steel 304 is the benchmark. It's what you want when you're dropping top dollar on a system like this, because ultimately it's gonna be the best at reducing corrosion, and it's gonna be the best at long-term durability. Far better than aluminized steel, and even 409 grade stainless to a certain extent. And you might pay a little bit extra for this, but ultimately Stainless Works does a great job of keeping this system pretty reasonable despite the premium build. So what is reasonable? Well, this system is hovering right around that $1,000 price-point, which in my opinion is very solid, given the level of craftsmanship and the level of materials. Now, if you wanted something with similar build quality and similar materials, such as Kooks, Corsa, or even Borla, you're gonna be spending a lot more compared to the Stainless Works here. And on the topic of installation, guys, again this one's not gonna kill you. One out of three wrenches on the difficulty meter, maybe an hour or two in the garage or driveway before you're making some noise. This one's gonna require some basic hand tools, including a basic socket set, an impact gun if you have one, whether it be air or cordless, and maybe an extra set of hands to help you muscle around a few large pieces. Now, as far as removing your factory system, basic clamps there, guys. Nothing crazy. You might want to get your extra buddy in hand here, or help you out removing that factory system, because it is a little big and it is all one piece. After that, simply install the Stainless Works system in reverse order, starting from the front to the back of the car. And again, you should be wrapped up in a couple of hours from start to finish. As for my final thoughts here on the X-pipe version of the Stainless Works LMF, well it definitely lives up to its name as being one of the loudest systems available for your Coyote powered GT. It's gonna give you a great build, and some of the best materials in the category, all for a price that's very reasonable, given the competition. So that's my review of the Stainless Works LMF Retro Three-inch system, which you can find right here at

      Product Information

      Features, Description, Specs & Installation


      • Aggressive Muscle Car Exhaust Note
      • Retro Chambered 3" Core LMF Mufflers
      • 3" Diameter 304 Stainless Steel Tubing (Steps Up from 2.5")
      • Mirror Polished 304 Stainless Steel Tips
      • Includes X-Pipe and (2) 4" Tips w/ Chambered 3" Core Resonators
      • Direct Fit Replacement Upgrade
      • Designed and Manufactured in the USA
      • Fits 2015-2017 GT Fastback Mustangs with Factory Manifolds


      Mustangs Should Roar. Leave behind the whispery whine of the factory exhaust and let your Fastback Pony roar. The Stainless Works 3" Retro LMF Cat-Back Exhaust with a factory-connect X-pipe will give your 2015-2017 GT Mustang that aggressive, deep, retro inspired growl you crave. In addition to enormous sound, X-pipes typically deliver more power higher in the RPM band. Enhance your S550 GT with killer sound and better performance with this LMF System.

      Retro LMFs. This 3" Cat-Back Exhaust from Stainless Works features retro chambered LMF mufflers and resonators with 3" cores, resulting in a much louder, more dominant rumble than the 2.5" core version. Loud and proud is the name of the game with this SW Retro LMF System.

      Quality Construction. Crafted from high quality 304 stainless steel for its superior durability and corrosion resistant characteristics, this 3" mandrel-bent system steps up from its 2.5" connection point to provide exhaust gasses a bigger, smoother outlet and enhance horsepower. Not only will this Retro LMF Cat-Back deliver outstanding sound and performance, it's finished off with two 4" mirror polished SS slash cut conical double-wall tips for sharp visual appeal.

      Direct Connect Install. The Retro LMF Exhaust System comes with all of the necessary hardware, hangers and clamps needed for installation. It's a direct fit, bolt-on replacement upgrade that connects directly to the OEM factory manifolds without any modifications needed.

      Application. This Stainless Works 3" Retro LMF Cat-Back Exhaust System with X-Pipe is a perfect upgrade for 2015-2017 Mustang GT Fastbacks with either automatic or manual transmissions. Requires the factory exhaust manifolds for proper fitment. Not compatible with convertibles or long tube headers.

      Fitment: 2015 2016 2017 Details

      Stainless Works M15CBX-LMF

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Right Muffler Assembly
      • (1) Left Muffler Assembly
      • (1) X-Pipe Assembly
      • (1) Right Intermediate Pipe
      • (1) Left Intermediate Pipe
      • (2) Resonator Tips
      • Hangers and Clamps

      Tech Specs

      Cat-Back Exhaust Specifications
      Piping Material:304 Stainless Steel Tip Material :Mirror Polished 304 Stainless Steel
      Piping Size:3" (steps up from 2.5")Tip Size:4"
      Muffler Type:Retro Chambered 3" Core LMFFitment:2015-2017 GT Fastback

      Customer Reviews (4)

        Reviews of Stainless Works Exhaust products have an average rating of 4.8 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • GT - 15, 16, 17

          Not Compatible w/ Convertibles Due to Different Bracing. Connects to Factory Manifolds Only

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