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

Item 387381
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Market Price $329.99 You Save 15% ($50.00)
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$279.99 (each)

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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.

    RTR

    Fitment: 2015 2016 2017 Details

    MPN# 387381

    CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

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

      Customer Photos (87) Submit Your Photo

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        Questions & Answers (24)

        5 Top Rated Questions

        Will this diffuser fit with a quad tip exhaust?

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

        Helpful (1)

        hi! may i know the box dimensions weight of this product? its for shipping purposes. thanks

        • Packaged weight is 5 lbs. Dimensions are: 44" L x 14.25" W x 5.25" H.

        Helpful (0)

        hi! may i know the box dimensions the weight for shipping purposes? thanks

        • The packaging occasionally changes over time for various reasons, so your best bet if you ever need these dimensions would be to contact our customer service team to make sure you are getting the most up-to-date answer.

        Helpful (0)

        I was Q and received no answer. So is there any rear diffuser's that will be offered in the future for the base model bumper?

        • At this time, we are unaware of any models in the works for base model bumpers.

        Helpful (0)

        It says this will fit Trim Levels: 200A/201A/400A/401A. Where can I look to see if I have one of these?

        • You can check in the owners manual or call a Ford Dealership.

        Helpful (0)
        10 More Questions
        Will this fit on the 50th anniversary edition GT? 1 answer
        Hello !! I don’t know very much about this , should I disconnect the battery to remove the bumper ? 1 answer
        Any idea on how I could get this to fit my v6 base model other than purchasing a premium bumper? 1 answer
        Will this fit a 2018 ecoboost (w/ PP)? 1 answer
        Will this RTR Rear Diffuser fit my 17 ecoboost with the performance package ?! Please let me know ! Thanks 1 answer
        Will this diffuser fit my 2015 V6 Mustang? (not premium) 1 answer
        In the video, I’m not sure whether it’s a cutting process, so dose the installation needs to destroy the original bumper? Thanks 1 answer
        When will we get the option for the non-premium mustangs? (RTR Rear Diffuser) 1 answer
        Would this work with a tow hitch (used to haul mountain bikes)? 1 answer
        Hi I'm not sure what trim my car is. Any idea how to find out visually? 1 answer

          Customer Reviews (79) Write a Review

          Overall Rating 4.9

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:$250-$500

          • Fit 4.972603 5.0
          • Appearance 4.972603 5.0
          • Bang For Your Buck 4.424657 4.4



          • 5/5

            Installation Time: Afternoon

            November 12, 2019

            PITA Install but good looking

            Install was going well as far as unscrewing some of bolts and push clips. However, when I ran into unclipping the original diffuser, all frustration kicked in. You quickly realize why they suggest removing the bumper. The clips wouldn't be as hard to get off if you were standing up and had good leverage, but being underneath the car trying to slide and pry the clips off; quickly became a daunting task. Having a second pair of hands definitely helps if you intend on keeping the bumper on.

            Shadymouse

            Year: 2017 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $250-$500

            September 12, 2019

            Rtr rear diffuser looks AGGRESSIVE

            Awesome look to make the rear end more aggressive. I highly recommend to buy this along with the Raxiom revser light/running light. It's the perfect combo.

            HpablaH

            Year: 2016 Submodel: GT

            Helpful (1)

          • 5/5

            May 01, 2019

            Great Diffuser!

            Relatively easy install (highly recommend buying a Dremel for this), and definitely worth the effort. Looks great and makes the rear so much more aggressive.

            DerekB

            Year: 2015 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Afternoon

            April 03, 2019

            RTR Diffuser

            Fit n finish looks factory. Love the new styling, and installed just as advertised.

            Evan

            Year: 2017 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            March 18, 2019

            Most aggressive feel!

            When I installed my RTR rear diffuser it was exactly what I needed to toughen up the look of my rear end. Just about all my mods are RTR so I am very loyal to an amazing brand. Install was fairly simple, little scary cutting into the rear bumper but doing so was a lot easier than it sounded. The only annoying part was trying to clip in the new rear diffuser with the stock one. The clips were stiff and required a bit of muscle to get them in, but they will eventually pop into place. 10/10 would recommend

            AndrewC

            Year: 2015 Submodel: GT

            Helpful (1)

          • 5/5

            Installation Time: Less than 1 Hour

            February 08, 2019

            RTR rear diffuser

            This diffuser looks great fit and finish perfect easy install

            TimE

            Year: 2015 Submodel: GT

            Helpful (2)

          • 4/5

            Installation Time: Afternoon

            February 01, 2019

            Perfect fitment

            OEM grade in fitment and finish. Completed satisfied with how this diffuser makes the rear of the car look like how it should have come from the factory. The only thing that was tricky was getting all the factory clips to release to remove and install the new diffuser, which made the install time a bit longer than it really should have been.

            PeterB

            Year: 2017 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            December 18, 2018

            RTR rear diffuser

            This make the back of my Mustang look more aggressive and a way better style. I’m really impress with this product. The fitting and installation is great.

            OrandeC

            Year: 2017 Submodel: V6

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            September 18, 2018

            Awesome new look!

            Install took quite longer than expected. But once installed it's all worth it! Definitely changes the look of the rear-end. Diffuser complements the lines of the Stang and matches perfectly to the Stock black linings. Highly recommended!

            RobertD

            Year: 2017 Submodel: EcoBoost

            Helpful (6)

          • 5/5

            Installation Time: Afternoon

            September 08, 2018

            Huge improvement

            Looks much better to clear up the excessive paint matching the S550 forced on all the models. Very aggressive look, not nearly as difficult as anticipated. If you have done any moderate jobs on your S550 this will be easy, just jump into the two cuts you'll have to make and dont be worried, its not a finesse job. Love the new look. Takes approximately 2 hours.

            Kris

            Year: 2015 Submodel: GT

            Helpful (7)

          • 5/5

            Installation Time: Afternoon

            August 22, 2018

            Wonderful Piece Of Art

            Very Happy with this purchase I made for my car. Great quality piece that gives your car a unique RTR look for your Mustang. This valance also changed up the look of the back end of my Mustang. I would recommend this for an afternoon install but the instructions are straight forward.

            AntonioA

            Year: 2015 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Less than 1 Hour

            June 27, 2018

            RTR diffuser

            Very happy with my purchase,great quality piece that gives your pony an aggressive look.

            RichardK

            Year: 2016 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            June 15, 2018

            RTR Rear diffuser 2015 Gt

            Very pleased with the results. Cleaned up the rear of my GT. Install was straight forward, but clip removal is a bit of a challenge, but not to bad. I used a flat head screw driver to push the clips from the backside, just be easy..

            MacP

            Year: 2015 Submodel: GT

            Helpful (9)

          • 5/5

            Installation Time: Afternoon

            June 08, 2018

            Amazing!!!

            This valance really changed up the look of the back end. Instructions were very straight forward and easy to follow. 10/10!

            Darron757

            Year: 2015 Submodel: GT

            Helpful (9)

          • 5/5

            Installation Time: Afternoon

            May 23, 2018

            RTR Rear diffuser

            Another awesome product from RTR. I love the look and it really gives the rear of the vehicle the aggressiveness it needs. Easy install and perfect fit. Thanks AM!!

            BradB

            Year: 2017 Submodel: GT

            Helpful (8)

          • 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 (11)

          • 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 (10)

          • 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 (10)

          • 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 (10)

          • 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 (11)

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