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

Market Price $443.99 You Save 10% ($44.00)
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$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! Install the same exact Rear Diffuser that is featured as original equipment on the Ford Mustang RTR to your very own late model muscle car. Designed and developed by Vaughn Gittin Jr., this Diffuser will add a modern, yet aggressive race inspired appearance to your ride.

    Quality Construction. RTR manufactures its Diffuser from OEM quality, high pressure injection molded, high-strength thermal plastic olefin (TPO) for its long lasting durability. This RTR Rear Diffuser features a grained texture for an OEM look and to hide rock and stone impacts that occur during daily driving.

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

    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 2015-2017 GT and EcoBoost Mustangs equipped with the factory Premium Chassis Packages only (Trim Levels: 200A/201A/400A/401A).

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

    Fitment: 2015 2016 2017 Details

    What's in the Box
    • (1) Rear Diffuser
    Installation Info
    Tech Specs
    Will it fit my Mustang?

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    18 Questions / 5 Answers

    Ask a Question

    Will this diffuser fit with a quad tip exhaust?

    KevinG

    • The RTR Rear Diffuser, is not designed for a quad tip exhaust and would require modification.

      JaHarrisAM

    Helpful (1)

    Any idea on how I could get this to fit my v6 base model other than purchasing a premium bumper?

    Chris89

    Will this fit a 2018 ecoboost (w/ PP)?

    John

    • The RTR Rear Diffuser has not yet been tested on 2018 Models. This only fits vehicles with the Premium chassis package, Trim Levels: 200A/201A/400A/401A

      Rob D

    Helpful (0)

    Will this RTR Rear Diffuser fit my 17 ecoboost with the performance package ?! Please let me know ! Thanks

    LaFigura305

    • This RTR Rear Diffuser will fit on Mustangs with trim levels: 200A/201A/400A/401A. If your performance package has one of those trim levels, it will work.

      AMJEFF

    Helpful (0)

    Will this diffuser fit my 2015 V6 Mustang? (not premium)

    RomyCheryZ

    • This RTR Rear Diffuser is specifically designed to fit 2015 to 2017 GT and EcoBoost Mustangs equipped with the factory Premium Chassis Packages only.

      Ricky36

    Helpful (0)

    In the video, I’m not sure whether it’s a cutting process, so dose the installation needs to destroy the original bumper? Thanks

    LingyuS

    • This RTR Rear Diffuser does require some light trimming of the factory bumper. Attached below is an installation guide that shows exactly what needs to be trimmed. https://www.americanmuscle.com/rtr-rear-diffuser-1516-manu-install.html

      AMJEFF

    Helpful (0)

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    Customer Reviews (64) Write a Review

    Overall Rating 4.9

    out of 5 stars

    Installation Time:Afternoon

    • Fit 4.982759 5.0
    • Appearance 4.965517 5.0
    • Bang For Your Buck 4.431035 4.4



    • 5/5

      Installation Time: Afternoon

      April 24, 2018

      Looks Awesome!

      Easy to install and looks so much better! I get looks and compliments everywhere I go

      Turbostang

      Year: 2015 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      April 18, 2018

      Excellent

      I love this product I’m so happy I purchased it for my car it could look any better.

      JonathanS

      Year: 2017 Submodel: EcoBoost

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      April 01, 2018

      RTR diffuser

      This part looks AMAZING. Very aggressive look. The install was a little bit of a pain in the a@and. Getting the factory trim panel off was the hardest thing of the whole install. But well worth it.

      DarkEagle

      Year: 2016 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      March 13, 2018

      Superior look

      This diffuser turned out better than I expected. Really gives the rear a manly look.

      MohammedS

      Year: 2017 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      March 10, 2018

      Lookin mean

      Just installed it, took about 2 hours, a couple set of hands would help. A light for under the car as well. Looks great.

      BrettD

      Year: 2016 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      February 21, 2018

      Taking care of the back end

      As always it was shipped very fast and the Quality was spot on very easy to put on makes the back end of my Mustang look very fast I am very happy with this

      JamesH

      Year: 2015 Submodel: EcoBoost

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      January 12, 2018

      Rear diffuser

      Fits perfectly, it’s honestly easy to install. I installed it myself in front of my house. It also comes w/ easy step by step instructions. It’s honestly a must get for a 15-18 premium mustang.

      DanielL

      Year: 2016 Submodel: EcoBoost

      Helpful (5)

    • 5/5

      December 09, 2017

      Finish the look !

      if you have a premium model Mustang, then this is for you. gives your Mustang the custom look. Installed by my local body guy in about an hour. fits in nice with the other mods from AM .go for it you won't be sorry ! photo to follow

      Smedlap

      Year: 2015 Submodel: EcoBoost

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      November 27, 2017

      The God of Rear Diffusers

      If your looking for the best looking most aggressive rear diffuse this is the one. Very easy to install, does require a little cutting to remove the stock diffuser but even that is too easy to do.

      CutterWolf

      Year: 2015 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      November 14, 2017

      stand out from the rear

      looks and fits perfect, would of been 100 satisfied if the products cost 300 not 400. purchased the Chinese version on ebay and it fit so loose. also the plastic did not match the rear diffuser and was much thinner than the original RTR diffuser. lesson learned, don't buy copies always go original, even if you have to pay more.

      RubenA

      Year: 2015 Submodel: EcoBoost

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      November 09, 2017

      Rear diffuser for 2016 Gt

      Love the new glossy look, looks just like the stock Gt rear diffuser that my Gt came with.

      AndresF

      Year: 2016 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      October 12, 2017

      RTR rear diffuser

      The RTR rear diffuser is an awesome addition to set off the back of the car. It is very aggressive and blends perfectly with the rest off my mods. You won't be disappointed with the looks. The product is well made fits perfectly! The install is not for beginners though. There is cutting involved, but its worth it when you're done. Just take your time.

      GSXRYDR

      Year: 2015 Submodel: GT

      Helpful (4)

    • 4/5

      Installation Time: Full Day

      October 08, 2017

      Silver17GT

      Looks good on the car but not the $ 400.00 you have to pay for it. I watched all the install videos and it looked easy to remove the stock valance. Removing the valance was a lot harder than what I watched on the video. The install was pretty easy. So I give it 4 stars.

      jla2837

      Year: 2017 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      September 01, 2017

      OEM Fit Finish- Very Nice

      I was somewhat skeptical about the match to the surrounding OEM trim when I placed the order. I was not disappointed, it matches very well. Easy to install, it would be really hard to mess up the cut that needs to be made. Good time to make the change is when you're upgrading the exhaust. Very easy access without the pipes in place. Little pricey, but I'll pay a little more not to be disappointed. Packaging was also great, box was a little beat up, but it was wrapped and protected well.

      JohnM

      Year: 2017 Submodel: GT

      Helpful (4)

    • 4/5

      Installation Time: Afternoon

      August 22, 2017

      Aggressive look

      Makes the rear end look more aggressive. Great addition

      Jesse

      Year: 2015 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      August 08, 2017

      Wow looks much better really does

      Just be careful when you get the color part the tabs are a real bear..all other tabs and screws are not to bad and the cutting is easy..the back of my car looks great ..take your time ...youll be happy you did this

      StvrinoV6

      Year: 2017 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      August 02, 2017

      Custom Touch!!

      Absolutely love this item. Looks great and aggressive. Really adds that custom look where the stock diffuser just looked mediocre. The only dislike is the price. If it was priced around $300 it would no doubt everyones choice.

      Andy

      Year: 2016 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      July 27, 2017

      Perfection!

      The RTR rear diffuser fit absolutely perfectly the instructions were spot on and it took roughly a hour and a half! The material matches perfectly with the rest of the black trim! Absolutely zero complaints!

      2015GTBrad

      Year: 2015 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      May 22, 2017

      Looks aggressive and easy to install

      Picked up this diffuser for my girlfriends s550 . It was easy to install. Took about a hour to install and it looks really mean! Great upgrade.

      Oscar

      Year: 2017 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      May 07, 2017

      Excellent product...

      ... Since I have a black 2016 Mustang GT, I didn't have to deal with the unsightly color contrast on the back bumper that I would have if, for instance, I had a Triple Yellow or Race Red. Consequently, I didn't have the burning need to change diffusers but, after installing the RTR Side Rocker Splitters, I felt the back end was missing something. The RTR Rear Diffuser really completed the lines created by the tail section of the side splitters. I would say the perfect compliment.

      Lonewolf3307

      Year: 2016 Submodel: GT

      Helpful (4)

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