Free Shipping On Orders Over $49. Details

Talk to a Mustang Enthusiast
M-F 8:30A-11P, Sat-Sun 8:30A-9P
Win $4,000 in Store Credit! Enter Now >

MP Concepts GT350 Style Rear Diffuser (15-17 GT Premium, EcoBoost Premium)

Item 397418
Call a Mustang Enthusiast at 1-877-887-1105
M-F 8:30A-11P, Sat-Sun 8:30A-9P
Market Price $419.99 You Save 33% ($140.00)
Our Price

$279.99 (each)

+ $49.00 Handling Fee with FREE Shipping

Will this fit your Vehicle?

Select a different vehicle Help?
Update or Change Vehicle

Item Options

In Stock

Ship to: Ashburn - 20149
Sorry, please enter a valid US or CA postal code
We're sorry, zip can't be updated at this time.
    Create a list
    Add to New List

    Saved - View your saved items

    We're sorry. We couldn't save this product at this time.

    or use

      Video Review & Installation

      Hey, guys. Adam here with Today we're taking a quick look at and of course installing the MP Concepts GT350 Style Rear Diffuser available for the '15 to '17 GT Premium and EcoBoost Premium. First off, guys, you should be checking this out if you're looking for a bold exterior styling specifically at the rear end to get a little bit more aggression out of your S550 compared to your factory valance or diffuser. Now, this particular one here from MP Concepts is made to look a lot like the factory G3T50 style rear diffuser that accepts quad tips. Now, before we move any further, I wanna mention that we have this installed on our '15 GT, which of course comes with factory single tips. With that said, the MP Concepts rear diffuser does come with quad-tip inserts to accept a quad-tip exhaust. If you're using a factory single tip exhaust, you can pick these inserts up separately that I've installed here from MP Concepts that are specifically for single tip exhausts. So, you have options, I just want you to know that what you see here is sold separately. This is the MP Concepts single tip insert, but it comes with the double tip insert.With that said, guys, here this is made to look like an OEM quality part, it's made using the exact same injection molded plastic as the factory one. And it's made using the same OEM CAD data from Ford. So, it's a perfect fit all the way around, it snaps right into the factory mounting locations. It does also work with factory backup sensors, but that may require some drilling afterwards to make sure they can transfer over properly. With this guy here, you're gonna be able to transfer over your factory reverse light that's gonna bolt right up there using some new spacers. And you can transfer over the markers here at the rear end as well. This guy of course has a bolder center section right where the reverse light is there compared to the factory Premium rear valance, which has a color match section in the middle with two fins. Now, there's a couple of different exterior diffusers you can pick up in the category. This one here, in my opinion, is the closest to looking OEM, it's something of course we see on the OEM GT350. So it goes hand in hand on this body.Now, this guy comes in right around 265 to 270 bucks, making it a pretty affordable way to get a very big change and styling at the rear. Especially if you're converting your factory single exhaust to a quad-tip exhaust. That quad-tip exhaust can be in the form of a full catback or an axle-back. Or you can pick up some of the MP Concepts quad tips that bolt right up to the inside of this particular diffuser. I will say though a lot of those tips do require you to fully cut off your factory single tip in order for it to work. But if you're looking to cut some cost, that's a really cost-effective way to do so.Now, the install for this I'm gonna give two out of three wrenches are difficult to meter not because it's overly difficult, but there are some specialty sections that you have to keep in mind. Getting this diffuser installed means you have to take the factory one off, which means you have to cut off the factory paint matched section. Now, ours was already cut on our '15 GT. So, I'm gonna be showing you guys exactly where to make the cuts but do know that ours have already been cut in the past. But I'll show you guys that in just a little bit. At the end of the day, they're two very small straight cuts that you're making. It's something that you can even put back to stock after the fact even if it's cut, so it still goes back together perfectly fine. After that, it's just a bunch of really simple hand tools required, it'll take you about two hours from start to finish to get the whole thing tackled. Now, of course, you wanna remember that you want to pick up the single tip insert if you're using the factory single tips like we are. Now, I'm gonna show you every step of this process, what do you say we get started?All right, getting right to it, you got to put your vehicle up in the air, whether that be on jack stands on the ground or using a lift like we are here. The lift makes life a lot easier, but we have access to that, if not, the floor will work just as well. The first thing you're gonna do is start at the rear here where the bumper connects to the inner wheel well liner. There are three 7-millimeter bolts you can access from the wheel well, you're gonna do that on both sides, and then everything else is just underneath. So, I'm starting with a 1/4-inch ratchet, a small extension, and a 7-millimeter deep socket. There are two 7-millimeter bolts right here facing out that way, and then there's one facing directly up and down, which we're gonna tackle third. So, grab your ratchet, get those two off here. They're gonna be very difficult to see but if you just peek your head in there, they're pretty easily visible from the inside. So just get those two out of the way then we'll move on.All right, so we're just peeking your head in there. There's one right here, so I'm just gonna work that guy off. All right, so there's one. Directly below it there's another. All right, so with that out of the way we can peel this guy back. I'm just gonna prop it up behind that tire, and it's sticking straight up and down. There's another guy down here so we're gonna get that off as well. All right, so here's the one facing directly up. There are two more right here and here, but we can access them from underneath. This is the last one in the wheel well. All right, so we got this guy out. Now we can repeat that on the other side and then head underneath, do the rest.All right, so next we have the vehicle up in the air a little bit higher, we're doing the exact same thing we did over here. We can see we have one more 7-millimeter here facing up, but there's also one in the middle, and you can't see it past this plastic trim piece, but you can go right on top of it and get it off. So, we're gonna do that for both of these on both sides. So, there's that, do the same thing for this one. All right, now you can see on this bracket here, there is a plastic pushpin clip. There should be two, ours is missing one. That's pretty common nowadays, especially if you have a used vehicle. So, you wanna make sure you're getting both of these off if you have two. I'm gonna get this remaining one off here. I'm gonna use a panel removal tool for this.All right, so now we're looking at our factory reverse light. Let's unplug it as the first step. Just have that wire dangle there. There are four Phillips head screws holding this on, two here at the bottom, two at the top. The top is a little bit more difficult to see, but it's still easily accessible. You can use a Philips head screwdriver, I also have a Philips head bit on my impact gun, so that's what I'm using here. Now we can pull this out and set it aside. Now, on the valance, we have two of these pushpin clips, one on each side, grab your panel tool and get these guys off. All right, now we can pull off the actual valance trim. So, you're gonna start from the outside and work your way around, pulling straight back to disconnect.All right, at this point, this pre-painted color-matched valance piece has to be cut off. Ours is already cut off from the past, we've done this before. So, just know that ours has been cut, but you will have to cut this guy off. It's molded to the bumper all in one piece and you can see straight across where we made that cut. So, originally, it sat here just like that, you can grab a body saw or really any cutting tool that you have and you feel comfortable with just to cut a straight line right through the middle there and it detaches and comes off. If you ever wanna go back to stock, just like we had it here, it can literally just sit in place right up against it. And when that plastic trim is back on the factory valance it holds it back in place. So, even though it's cut off, it can still go back to stock, no problem. Ours is already cut, so we're just gonna move forward.All right, so we got our factory diffuser off of our '15 GT Premium and it's on this rack here underneath of our new GT350 style rear diffuser from MP Concepts. I wanna go through some similarities and differences between the two. And I got to say aside from the actual construction materials and fitment, it's all completely different. First thing I wanna talk about here is the way that your factory GT Premium here has the pre-painted or color-matched valance in the center with those individual fins on each side. Now, that looks pretty good from the factory, but beefing things up to get a really bold rear end, which we know the GT350 Mustang has, you can see that replicated here in the top. So, it's getting rid of that paint match section and it's really accentuating that top curve. You can sort of see that happening here but that's covered by the trim that you see above. So, the fact that this is so bold and so much bigger than factory paint section there is such a huge eye-catcher for this one. Aside from that, instead of the fin design that you get down here, you're actually getting these honeycomb mesh inserts there. So, you have three of them, one right below the reverse light and one on each side. Now, I will point out that these are not functional, they are blocked off so it's not something airflow is gonna be able to cut through. But for visuals purposes, it is a lot bolder than the factory one. Aside from that, you get a little bit of a taller look above the factory reverse light, which otherwise had a very small section there. And at this point, guys, we have a couple of things we have to transfer over from the factory diffuser, including those marker lights. And of course, we're gonna install the reverse light here before we get on the car.All right, first, let's focus on a reverse light. Now, you'll see that there are two tabs here for the factory screws. But the bottom here has these two little snap-on tabs. Grab the spacers or adapters here, you're basically gonna push those right into place on the back end. And they'll just sit in there nice and snug. From there, we can put our reverse light into place, grab those factory Philips head screws, and we're gonna screw those into the spacers I just slapped on there. I'm just gonna put them on lightly by hand. Same thing at the top and then tighten them down. Now, for this, you can use a Phillips head screwdriver. I have a Philips head bit on my impact gun. You just wanna make sure you're not over-tightening them, just get them snug because you don't wanna strip out that plastic. All right, now it's in there, we can move on to the marker lights.Now we can focus on the reflectors and marker lights. So, what do you say we grab a 10 socket and get this nut off the back end? All right, you wanna hold on to that because that is going to get reused. Push on this tab here to snap it out of place. Just like that. We could transfer it over. All right, so now we can do the same thing here. You're just gonna basically push the tab in. Make sure it snaps all the way in, you hear that click, then you can put that factory nut back on and tighten it down. Again, the same case, you don't wanna over-tighten it, just get it snug. Same thing on the other side.At this point guys, I just wanna reiterate something, if you have a quad-tip exhaust and you wanna use the quad tips for the new diffuser, you wanna use what's included in the kit, these inserts. As you can see, the insert accepts quad tips. But if you don't have quad tips like our '15 GT, which uses its factory single tips, you can pick this adapter insert up separately from MP Concepts, which changes it from a quad-tip exhaust diffuser insert to a single tip. That's what we're gonna be using here. This is sold separately not included in the kit and we're gonna using that here. But if you have a quad-tip continue with what's included in the kit, the install is exactly the same, just a slightly different design to accommodate two tips.All right, so now we can line up. Again, I'm using the single tip sold separately, but it's the same thing for the quad tips included in the kit. We're just lining them up to the tabs on the side here and snapping them into place. All right, you just wanna seat these all the way back, make sure you hearing that click so it holds itself in place there. And then we can do the same thing on the other side.All right, so now last step of transferring things over here, we have to take these metal U-nut clips off. You can use a flathead screwdriver if you need to. Ours are pretty loose right now so I'm just gonna pull them straight off and transfer them over. This step is pretty easy. Just going over to these tabs on the side there, inserting the clips. You just wanna make sure the threadings line up to the open hole there and make sure the threads are facing up. Repeat on the other side, and now we can install in the vehicle.At this point, it can be a little bit tricky, but you're basically gonna line this guy up, insert those exhaust tips in, and again, we're using the single exhaust tip inserts, but yours may be dual. Once you have it there, you're gonna lift it up so it snaps in the tabs above the tips, and just work your way around. All right, so now that we have this on, we're gonna focus on putting our factory three 7-millimeter screws back in place. And we're just gonna start by hand threading those guys in just to get them started. Grab your 7 socket and tighten those three down. Now we have to put the pushpin back through this bracket but we have to bend this guy upward. So, you have to bend it on that crease, line up those holes, grab your pushpin, and put it back through. Now, if you remember, we're missing one, but you should have two of them there. Repeat this entire section on the other side.All right, so now we just have two more in our wheel well. Grab your factory 7 millimeters, put them back through, grab your extension and 7 socket and tighten them down. Repeat on the other side and we have one more step. All right, last step here, pull down on the diffuser just to get enough clearance for the reverse light and plug it in. It's a little bit higher up now so it's close to this pinch weld here. In which case you just need to pull down, snap it in, and you're good to go.That's gonna wrap this one up, guys. If you're looking to pick up the MP Concepts GT350 Style Rear Diffuser for your '15 to '17 GT and EcoBoost Premium, you can pick yours up right here at

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Aggressive GT350 Inspired Styling
      • Durable Injection Molded ABS Material
      • Features a Stippled Grained Texture
      • Straight Forward Installation - Cutting Required
      • Backup Sensor Compatible
      • Intended for use with Aftermarket Quad Exhaust Systems
      • Designed for Premium Chassis Packages Only (Trim Levels: 200A/201A/400A/401A)
      • Fits 2015-2017 GT Premium and EcoBoost Premium Mustang Models


      Race Inspired Appearance. Add a serious race look to your 2015-2017 Mustang with the MP Concepts GT350 Style Rear Diffuser. This is designed to fit only premium bumpers, but it will enhance the whole look of your Pony thanks to durable construction and personal touches.

      Quality Construction. MP Concepts manufactures their GT350 Style Rear Diffuser from injection molded acrylonitrile butadiene styrene (ABS) plastic using the original OEM CAD data from Ford to ensure a perfect fit. ABS is an extremely strong material known for its light-weight, superior durability and impact resistance - making it perfect to withstand the hazards of daily driven vehicles. This Rear Diffuser is completed in a fine grained stippled texture for a factory look that helps to hide the appearance of rock and stone impacts.

      Straight Forward Installation. Installation of the MP Concepts Rear Diffuser is simple and straight forward. However, it will require permanent modification to the stock rear bumper cover to remove a section of the factory diffuser. Installation can be completed in about two hours. Reuses factory reflectors.

      Backup Sensor Compatible. This MP Concepts Rear Diffuser can be installed on Mustangs equipped with or without factory installed back-up sensors and will not affect sensor operation.

      Optional Single Exhaust Outlet Insert. If you love the aggressive good looks of the MP Concepts GT350 Style Rear Diffuser, but are running a standard single exit exhaust system on your 2015-2017 Premium Package Mustang, check out these Single Exhaust Outlet Inserts from MP Concepts. The MP Concepts GT350 Style Rear Diffuser was designed with Quad Exhaust Systems in mind, but by installing a set of MP Concepts Single Exhaust Outlet Inserts your single exhaust tips will look right at home in the diffuser. Sold separately - see buy together options above.

      Application. This MP Concepts GT350 Style Rear Diffuser is specifically designed to fit 2015-2017 GT and EcoBoost Mustangs equipped with the factory Premium Chassis Packages only (Trim Levels: 200A/201A/400A/401A). Intended for use with aftermarket quad exhaust systems.

      Please Read. If you are having trouble determining what style bumper your Mustang is equipped with please refer to the comparison image above.

      MP Concepts

      Fitment: 2015 2016 2017 Details

      MP Concepts 397418

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Diffuser Panel
      • (2) Reverse Light Brackets
      • (2) Tail Pipe Inserts

      Tech Specs


      Customer Reviews (16)

        Reviews of MP Concepts Exterior products have an average rating of 4.2 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • EcoBoost - 15, 16, 17
          • GT - 15, 16, 17

              Related Mustang Categories