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RTR Rear Diffuser (15-17 GT Premium, EcoBoost Premium)

Market Price $443.99 You Save 10% ($44.00)
Our Price

$399.99 (each)

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  • Item 387381
  • MPN# 387381

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Features, Video & Details

  • RTR Signature Modern Aggressive Styling
  • Injection Molded TPO Material
  • Features a Grained Texture
  • OEM Fit and Finish
  • Straight Forward Installation
  • Backup Sensor Compatible
  • Fits 2015-2017 GT and EcoBoost Mustangs
  • Designed for Premium Chassis Packages Only (Trim Levels: 200A/201A/400A/401A)

Review & Installation Video

Review & Install Video

Hey guys, Justin with AmericanMuscle.com here, with my detailed review of the RTR Rear Valance Diffuser, fitting your premium package 2015 and up Mustang. So, who is this rear valance going to be for? Well, I would say it's going to be for anyone out there who really enjoys what Vaughn and his team at RTR have done with the S550, in regards to overall styling, and maybe wants to emulate that on his or her own ride. In addition, I'd say it's an excellent option if you're like me and you really didn't enjoy the factory color-matched rear valance, and want to replace it with something that's going to be a little bit more aggressive. Now when talking with Vaughn directly about his inspiration for the new RTR Mustang, he made it very clear to me that he wanted to do something pretty crazy with the rear of the car and give it more of an exotic look, in his own words. So by going with this fin-style rear diffuser valance, he definitely accomplished that and gave it more of a race car-inspired look in the rear. Now I think personally this thing looks a lot better when paired with the RTR rocker splitters, but again that is up to you, as it is going to add roughly 300 bucks to the final price tag. On the topic of price guys, this thing is definitely going to come in at the top of the food chain in regards to rear diffusers. Here on the site, it will be nearly double the price of the Roush rear valance, however you have to keep in mind that Roush rear valance can only be used with a quad-tip exhaust setup, so you have to factor that into the price. On the other hand, the RTR rear diffuser here can be used with your factory or aftermarket single-tip exhaust system, so you don't have to worry about anything there. Breaking down some of the finer details here, guys, you will find a durable, injection-molded ABS plastic for the build, and it has been finished off in the same textured grain black plastic as the rest of the exterior plastic on your S550, such as the chin spoiler, lower rockers, things like that. I do want to remind you, this will only work on premium package rear bumpers, as they are a little different from some of the base cars, so definitely don't forget about that. And also keep in mind, this thing will work with factory backup sensors, should not interfere with their operation whatsoever. When it comes time to get dirty, guys, here's what you need to know. Now, there is some permanent modification needed to get this thing installed. Basically you're going to be cutting off that color-match portion of the factory valance and replacing it with the RTR unit here. So an air saw, Dremel, something similar is going to be your best friend here. You're definitely going to need a 7-millimeter socket, along with a panel removal tool. Now, it probably sounds a lot more complicated than it really is, but nevertheless since there is some cutting involved, I'll call it two out of three wrenches on the difficulty meter, and maybe a couple of hours from start to finish to get this thing installed. So to wrap up, the RTR rear diffuser, or rear valance, guys, I really like what this thing does to the rear of the car. My one major pet peeve with the S550 from an appearance standpoint when it was released, was that color-matched factory valance. This thing totally replaces that, fixes that, in my opinion, and adds some aggressive styling to boot. So be sure to check out more from RTR for your S550 here at AmericanMuscle.com.

Ready To Rock! Add the same exact Rear Diffuser that is featured as original equipment on the Ford Mustang RTR, designed and developed by Vaughn Gittin Jr., to your very own late model muscle car for a modern aggressive race inspired appearance.

Quality Construction. Manufactured from OEM quality high pressure injection molded high-strength thermal plastic olefin (TPO) for it's long lasting durability, this Rear Diffuser features a grained texture for an OEM look and to increase longevity against rock impacts from daily driving.

Straight Forward Installation. Installation of the RTR Rear Diffuser is simple and straight forward, but will require permanent modification to the stock rear bumper cover to remove the factory diffuser.

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

Application. This RTR Rear Diffuser is specifically designed to fit 2015 to 2017 GT and EcoBoost Mustangs equipped with the factory Premium Chassis Packages only (Trim Levels: 200A/201A/400A/401A).

Fitment: 2015 2016 2017 Details

What's in the Box
  • (1) Rear Diffuser
Installation Info
Will it fit my Mustang?
  • GT - 16, 15, 17
  • EcoBoost - 16, 15, 17

Fits Premium Chassis Packages only (Trim Levels: 200A/201A/400A/401A)

People Who Bought This Item Also Bought

Most Helpful Reviews

5/5
Diffuser

Looks really good! Didnt take long to install at all! Would highly recommend it!

Helpful (1)

5/5
Looks awesome

Makes my pony looks more aggressive The installation it's easy if you have the right tools i recommend a friend to help you with it took me around three hours

Helpful (1)

Overall Rating 5 out of 5 stars
Read All 46 Reviews

Customer Photos (32) Submit Your Photo

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10 Questions / 6 Answers

Ask a Question

Hi I'm not sure what trim my car is. Any idea how to find out visually?

DeepinderP

  • You can get in contact with your Ford dealership and give them your VIN number. They will be able to tell you exactly what package is on your car.

    AshleyK

Helpful (0)

Will this work on A Mustang gt premium

123minh

  • This will only work on the Mustangs that are equipped with the factory Premium Chassis Packages. the trim levels it will fit on are 200A, 201A, 400A, & 401A.

    KevinD92

Helpful (0)

Has this been tested as functional?

wildcatgoal

  • This diffuser has not been tested for actual functionality and is intended for styling only.

    AMSam

Helpful (0)

Will it fit my 2016 v6 if I changed the rear bumper cover from base molde to premium one?

YoooooooTim

  • If you decided to remove the base bumper on your V6 with the bumper from the Premium GT or EcoBoost, you will be able to install the RTR Rear Diffuser on your vehicle.

    AMMatt

Helpful (0)

What colour is this diffuser, it looks grey in some of the photos?

thedalejrfan

  • The RTR Rear Diffuser (15-17 GT Premium, EcoBoost Premium) will be a black grained texture color.

    Ricky36

Helpful (0)

Not sure if I missed it in the video or not, but is this valance paint-able? My guess is no, but it never hurts to ask.

ChrisH

  • This Valance has a grained texture. It may require lots of prepping and priming in order to have a perfect paint job. I suggest asking around at local body shops if they are able to paint injection molded TPO material that has a grained texture.

    AshleyK

Helpful (0)

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Customer Reviews (46) Write a Review

Overall Rating 5.0

out of 5 stars

Installation Time:Afternoon

  • Fit 5 5
  • Appearance 4.975 5.0
  • Bang For Your Buck 4.45 4.5



  • 5/5

    Installation Time: Less than 1 Hour

    February 27, 2017

    Diffuser

    Looks really good! Didnt take long to install at all! Would highly recommend it!

    Bushguts

    Year: 2015 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    February 24, 2017

    Looks awesome

    Makes my pony looks more aggressive The installation it's easy if you have the right tools i recommend a friend to help you with it took me around three hours

    M1sahagun

    Year: 2015 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    November 03, 2016

    RTR for the win!

    Great product here from RTR, fit and finish are amazing and it completely changes the rear end of any S550, hardest part of the install is the clips but even that isn't too bad. And only took me and my buddy an hour and a half to install. Just take your time and do it right and you'll be back on the streets. American muscle shipping was amazing as usual!

    Burge

    Year: 2016 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Less than 1 Hour

    October 24, 2016

    RTR diffuser

    The product is amazing and fit exactly how I wanted it to. I'm so happy with how it looks.

    Jonny

    Year: 2016 Submodel: GT

    Helpful (1)

  • 5/5

    October 22, 2016

    Fabulous OEM fit and finish

    Took about an hour to fit, much easier having the car up on a hoist. The fit is perfect and the surface finish is identical to the black factory rear skirt. I fitted this to an Australian RHD GT convertible and it offsets the triple yellow perfectly!

    Tedy

    Year: 2016 Submodel: GT

    Helpful (1)

  • 4/5

    September 26, 2016

    Aggressive look

    I installed the RTR diffuser in about an hour from start to finish. It looks badass. OEM fit and finish, much more aggressive look than the basic factory diffuser. Simple install besides some tough to reach screws. Only reason for 4 stars is because it's way overpriced. Overall, I love it.

    Knox

    Year: 2015 Submodel: GT

    Helpful (1)

  • 5/5

    September 13, 2016

    RTR Diffuser

    I love it. It was not that hard to install and it looks incredible. A much needed addition to the back of my 2016 over the color matched diffuser. More aggressive looking and it actually fits tighter than factory. Thanks American Muscle !

    GTForFun

    Year: 2016 Submodel: GT

    Helpful (1)

  • 5/5

    August 07, 2016

    Rtr diffuser

    It looks amazing on a lowered mustang. Makes the rear of the car look so much more aggressive Im really satisfied with this mod.

    Dennis

    Year: 2016 Submodel: GT

    Helpful (1)

  • 5/5

    July 15, 2016

    RTR Diffuser

    Well made and precise fit to the rear bumper. Very easy to install in about two hours. Don't be afraid to cut the old diffuser off you will like the look when all is done. I highly recommend this product.

    Stang84

    Year: 2016 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    June 10, 2016

    Awsome product

    The finish of this diffuser is awsome. My car now looks more aggressive. And give my car more sporty. Fitting time is 2 hrs. I recommend this product.

    Zozi

    Year: 2015 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    January 20, 2016

    Does it get any better than the RTR Rear Valance Diffuser?

    I think not... It goes without question that the new S550 platform is an absolute hit from Ford! Independent Rear Suspension, state of the art technology, the evolution of the Coyote motor, and not to mention the comfort!! This is the best production Mustang Ford has ever developed! It didn't take long for Vaughn Gittin Jr. to see the potential of this new platform and he went right to work in developing this incredible kit for us S550 owners! The installation took me about 2 hours, and while installing, I was taking pictures and documenting the process for an install guide. Very simple process which requires minimal tools, and very little preparation. What is most appealing about this Rear Diffuser, is not only the undeniably aggressive aesthetics, but the ease of install. No hacking and slashing here guys! Simple install that was a great time for me and my 8 year old son! This valance has completely transformed the look of my car, and I am anxiously awaiting some additional RTR parts to complete the package! When you are considering an upgrade to your new S550 Mustang, look no further than American Muscle for your RTR Rear Valance Diffuser!! 11 out of 10!

    ProjectWhitemare

    Year: 2015 Submodel: GT Bay Area, CA

    Helpful (1)

  • 5/5

    Installation Time: Less than 1 Hour

    January 18, 2016

    Best bang for your buck!!!!

    The product came nicely wrapped and protected the quality was great and fitment was excellent takes about 30min for install really makes The car look more aggressive and evil from behind

    5litershark

    Year: 2015 Submodel: GT Murrieta

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    January 05, 2016

    Very Happy

    I've been looking around for a Diffuser for sometime. I'm so happy I didn't get in any hurry to buy. Because this thing is just beautiful. Gives it that mean aggressive look at the rear that I wanted. As for the install, it was cake. I did the install by myself and had zero problems. Took right around one hour to complete. Diffuser does require you to cut a little. But don't let that scare you, its easy work. The quality of the product is great, fitment is perfect. Could be more happy.

    Cory

    Year: 2015 Submodel: GT terre Hautee, IN

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    December 23, 2015

    2015 Mustang RTR Rear Diffuser

    My name is Phillip LeVasseur and I just recently installed the RTR Rear Diffuser on my 2015 Mustang. The install was quite simple and with an extra hand, should take about an hour from start to finish. The diffuser changed the look of my rear end completely giving it a much more aggressive look. 10/10 in book!

    Phil

    Year: 2015 Submodel: GT Bakersfield, CA

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    December 12, 2015

    Great look!

    Took me and my brother a little over 1 hour for install on his car lift.Really gave it a more aggressive look.Very happy with the quality and fitment.

    Flip

    Year: 2015 Submodel: GT Phoenix, Arizona

    Helpful (1)

  • 5/5

    Installation Time: Less than 1 Hour

    November 11, 2015

    Very good product

    Very good diffuser. It did add that mean aggressive look to the car that i needed. This product does require you to cut. Nothing big but it is needed. Product did meet its required expectations definitely a must have!

    Ayeeefelix

    Year: 2015 Submodel: GT Miami, FL

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    February 10, 2016

    Awesome Addition

    Well they do not have an option to Check 1 hour and 18 minutes from getting the car off the ground and putting it back on the ground. seriously under 1.5 hours to install this. Quality of the product is great, fit is great, price is great. you really cannot go wrong. Adds a very aggressive look to the back of this car. Next up are the RTR Side Splitters.

    Danny

    Year: 2015 Submodel: GT ca

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    February 09, 2016

    This RTR Rear Diffuser is amazing!

    The first time I saw a picture of the RTR rear valance I thought it looked awesome, but I hadn't seen one in person so I hesitated to make the purchase. I wish I had never waited! It makes me grin so huge every time I see it now. It adds such an aggressive look to the car while still looking like something that could (or should) have come from the factory on a premium performance trim level of this car. Even my wife was impressed and she doesn't usually pay much attention to what I do to my vehicles.

    KG

    Submodel: GT Mobile, AL

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    January 29, 2016

    Easy Way to Toughen Up the Rear End

    When this RTR Diffuser first came out, I wasn't a fan. For some reason I just didn't like the viewing angles, and didn't want to lose the painted section of my OEM diffuser. After some though I decided to bite the bullet and pull the trigger on this diffuser. Just from opening the box I knew I made the right choice. This diffuser is of great quality and fitment, as with anything from JR over at RTR. Install took about 2-2 1/2 hours and only required a few common tools. Seeing it on the car I do not regret my decision what-so-ever. It really toughens up the rear end and creates a nice contrast with my Competition Orange GT. This is a must have for any premium S550 Mustang.

    TrevorW

    Year: 2016 Submodel: GT Inwood, WV

    Helpful (0)

  • 5/5

    Installation Time: Less than 1 Hour

    January 21, 2016

    boosted gt stang

    Looks killer. I would recommend it to anyone who wants to make your car look more aggressive

    gt

    Year: 2015 Submodel: GT

    Helpful (0)

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