2015-2017 Mustang MMD Rear Diffuser (GT, EcoBoost, V6 w/Non-Premium Rear Bumper) Review & Install

Hey, what’s going on, guys? Adam here with
AmericanMuscle.com. Today I’m bringing you a quick overview of the MMD Rear Diffuser
fitting all 2015 and newer GT and Ecoboost Mustangs with a non-premium rear bumper. The
MMD Rear Diffuser is gonna be for the 2015 and newer GT and Ecoboost Mustang owner out
there looking to improve the appearance of their non-premium rear bumper, to give it
the flair and style that the premium package S550s offer, without breaking the bank. It has definitely been a popular complaint
between the S550 shoppers out there who picked up the GT and Ecoboost non-premium packages,
that the rear balance was kind of left plain and simple from Ford. Now, this doesn’t offer
the exact styling and flair that the premium packages do, which is where MMD steps up to
the plate to take care of that, to give you that noticeable appearance the premium packages
offer. Just to give you a quick rundown if you’re
not aware, MMD, or Modern Muscle Design, is really one of the industry leaders when it
comes to exterior styling parts for the S197s and the S550s. Now, they offer a wide variety
of top of the line, high-quality parts to really change the look of your S550, like
the one I have here. This option for the non-premium rear bumpers will offer the same detailed
fin styling you would expect from the premium packages, offered in a matte black finish
with the fins protruding out much farther than stock. Now, for the materials, you can expect a durable
thermoformed ABS plastic. Now, in all honesty, this does feel a little bit thin and flimsy
in your hands, but once attached to your vehicle, it will stand the test of time and be durable
enough to handle whatever is thrown at it. This is finished in a matte black pre-painted
color option. It is not offered in a pre-painted option to fit your factory color, but you
could definitely take this to a custom shop of your own to get matched for your factory
paint if you want it to blend in a little more. So one thing I do want to point out here,
guys, is this will require you to make very, very minimal amount of drilling into your
rear bumper. Now, the drilling will not be visible in any way, shape, or form if you
do decide to remove this in the future, and it won’t affect any future styling options.
Now, you will be drilling into these two pre-drilled holes in the rear diffuser into the bottom
of your rear bumper, but again, if this is not something you’re looking to do to your
rear bumper, this option may not be for you. Now, with the holes you’ll be drilling, you
will be putting push pins into place, just to keep it held up there. But in addition
to that, to give it some added security, there is also pre-applied 3M automotive bonding
tape already put onto the back of the rear diffuser, just to give it some added security
and to make sure it stays in place once it’s on, until you’re ready to take it off. Now,
the 3M tape will not at all affect your factory rear paint, if you do decide to take it off
in the future. Now, for the guys out there who are still
interested, expect to be spending about $250 for the MMD Rear Diffuser, which, honestly,
in the grand scheme of things isn’t too terrible, considering the alternative is a full rear
bumper swap to the premium package just to get that premium effect, Now, this will save
you all from taking too bad of a beating, while giving you some bang for your buck with
that same premium package styling you are looking for. So, moving on to the installation portion,
as I mentioned before, this will require a little bit of drilling, so you will want to
have a drill and a proper bit on hand, as well as the pushpins, alcohol wipes and adhesion
promoter that is all included in the kit. So, first things first, you wanna take your
alcohol wipes provided in your kit and completely clean the factory rear valance, freeing it
of all dirt and dust to make sure the 3M tape can get a good bonding. Once the area is completely
clean, you can apply the adhesive promoter. Now, with the 3M tape backing still on the
back of the MMD Rear Diffuser, you want to put it into place and mark the center of the
pre-drilled holes on the tabs on each side, just to mark your drilling locations. From here, you wanna drill a 23/64th-inch
hole through the pre-drilled holes on the tabs into your rear bumper and put into place
your pushpins provided in the kit. It may be easier to do so if you jack up the car,
just to comfortably have enough space to do some drilling. Once the holes are drilled
and everything is in place, you can peel back the backing on the 3M tape and firmly press
it into place, making sure it’s lined up properly. Overall, this’ll take you about a half-hour
to an hour at the absolute maximum. I would definitely give this one a two out of three
wrenches on the difficulty meter, simply because it does require a little bit more work with
the drilling. Just to quickly wrap things up, guys, if you’re the owner of a 2015 or
newer GT or Ecoboost Mustang and you’re looking for a way to spice up your non-premium rear
bumper to give it that premium styling without breaking the bank on a complete bumper swap,
you might wanna check out the MMD Rear Diffuser, which of course is available right here at


only thing making me hold off is the 3m tape. I dont want the thing to rip apart after a year. For such a premium price I would expect a better solution not 3m tape

Great to have you as a part of the AM team. Just saw Justin in a vid the other day thanks for your response. I hope you love it there, must be an awesome place to work.

Do we have a date when this piece will be for sale again? Its important for my build im completing for spring….!!!!!! @AmericanMuscle

Too many retards who didn't clean their bumpers good enough before installing this diffuser. Try using more alcohol if need be, heat up your tape and then adhere it to the bumper and it will take without problems. I've had mine for over a year now and no issues whatsoever! I'm starting to get bored of this styling and might just modify the RTR diffuser to make it fit the base models???

I'm pretty sure the design could've been better to reduce air drag but it's too many idiots who bought these, installed them incorrectly without cleaning and using the adhesive promoter on the surface properly before adhering the 3M tape and losing their diffuser! I bought this in early 2016 when they came out and still have mine safe and secure on the rear bumper. I'll be getting the NEW NON PP RTR replica diffuser in the next few days and have wanted that part since it came out but it's $600CAD for the RTR and over $408.00CAD for that stupid MMD diffuser!

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