Roush Mustang Rear Valance Install (13-14)

Posted 3/25/2014 by Jeff Jimenez

Watch us give a 2014 Mustang GT some aggressive exterior styling with the Roush rear valance & exhaust kit.

FOLLOW: mustang , 10 14 mustang , video , installation , s197 , roush , exterior , exhaust , axle back

Add an extremely aggressive look to the rear of your 2013-14 Mustang with the Roush Rear Valance kit. This rear diffuser is designed to work with the Roush “squre” tip axle back exhaust kit. The combination of the Roush rear valance and axle back will give any 2013-14 Mustang GT or V6 a truly custom look.

Roush Mustang Rear Valance Install (13-14) - Roush Mustang Rear Valance

Installation of the Roush rear valance does require some cutting and minor modifications to your rear bumper. You can follow along in our install video as we walk you through the installation process. In the video we also install the Roush axle back kit (RSH-421410) and even give you quick sound clip of the Mustang exhaust!

This kit will work on 2013-14 Mustang V6s. You will simply follow the same instructions in the video; however, you will need to pick up the Roush V6 Axle Back kit for proper installation. You can find this axle back in the link below!


About the Video

Roush Mustang Rear Valance Kit & Axle Back Exhaust Install (2013-14 5.0L GT)

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Published on 2014-03-03
If you are looking to give your 2013-14 Mustang an aggressive and unique look, you need the Roush Rear Valance and Axle Back Kit. The Roush rear valance (diffuser) is designed to give an aggressive new look to your S197 and comes designed to clear the Roush square style tips found on their axle back kits. This rear valance and square tip axleback kit were made popular on their powerful supercharged 5.0L Roush RS3.

Follow along in this video as we show you how to install the Roush axle back and diffuser kit. Installation of the diffuser will require some simple cuts and modifications to be made to your rear bumper. Roush includes all the required templates for you to make precise cuts and modification.

The Roush mufflers featured on their Mustang Axle Back Kit will give your Stang a super aggressive exhaust tone that will match the new killer looks of the rear diffuser. We offer this Roush Axle Back & Valance Kit for GT/Boss 302/GT500s and V6 Mustangs.

Be sure to click on the link at the top to see our full line of Roush Performance Parts! SVE 5.0Resto
Add unique styling and aggressive sound to your 2013 or '14 Mustang GT, with this Roush performance rear valance and axle back kit. Because of the large rectangular openings, the valance does require cutting of the original bumper cover. But much like other Roush products, detailed instructions and all needed hardware are included. Follow along, and we'll show you what is required as we install this kit on our 2014 Mustang GT.

Open the trunk and remove the two plastic nuts and two pushpin type retainers. Release the truck trim panel. Disconnect the trunk light electrical connector, and remove the truck trim panel. Disconnect the right and left hand tail lamp electrical connectors.

Remove the three retaining nuts per tail light, and push the harness grommets through the body. And remove both the left hand, and right hand, tail lamps. Raise and support the rear of the car.

In the wheel well opening, at the front of the rear bumper cover on each side, there are three screws that need to be removed. Then release the center clips on both the left hand and right hand splash shield. From under the car, remove and discard the two retaining clips. Remove the four pin type retainers, two per side.

Remove the pin type retainers from each retaining arm. Pull outward on the left hand, and the right hand, side of the bumper, to release it from the body. And then fully remove the rear bumper cover. Unplug and pull the license light harness through the rear panel.

Remove the two reflectors and the center trim piece by depressing the retaining tabs. Cut out the provided template. Tape the template to the bumper cover. And mark the area to cut. Using a center punch, mark the center of the holes on the template.

Remove the template and use an 1/8 inch drill bit to drill the pilot holes. Finish the holes with a 1/4 inch drill bit. Cut off the area you mark, using the template. Mark the lines to be slotted on the bumper cover. And using a body saw, open up the slots.

Clean up your rough edges with a file and a sharp knife. Repeat all of these steps for the other side. Using the U-nut template, tape it in place on the back bumper cover. And using a center punch, mark the center of the holes on the template. Cut out the 9/16 and 3/8 holes out of the template, and trace the openings to be cut on the bumper cover. Repeat these steps for the other side.

Drill the marked pilot holes using an 1/8 inch drill bit. Then open the holes up, using a 3/8 drill bit. And on the slotted parts, use a 9/16 drill bit. Repeat these steps for the other side.

Cut out the center template for the valance panel, and tape it into position on the bumper cover, with the arrow pointing upward. Using your center punch, mark the center of the holes to be drilled. Remove the template, and use your 1/8 inch drill bit to open the pilot holes, and finish off with a 1/4 inch drill bit.

Mark your lines to be slotted, and use your body saw to open up the slots. Install the provided two J-clips into the holes on the rear bumper cover. Using the template for the right hand and left hand bumper cover mounts, hold it in place, and use your center punch to mark the center of the holes. Drill your 1/8 inch pilot hole, and finish opening the hole with a 3/8 bit.

Using rubbing alcohol, clean the bumper cover and the rear valence mating surfaces. Allow the alcohol to dry. And then apply 3M Adhesion Promoter to the rear valance, where the double-sided tape will be applied. Allow the adhesion promoter to dry for at least a minute. Install the double-sided tape on the backside of the rear valence, leaving the red film facing upward.

Peel the backing off of the double sided tape. Place the rear valance onto the bumper cover, and install the 12 U-nuts, two W-clips, and two eight millimeter bolts onto the back of the valance. Reinstall the two rear reflectors. Using your paint pen, it is also necessary to mark and trim a few areas on the rear bumper impact absorber.

Take your body saw and completely remove them from the rear bumper impact absorber. Lubricate the muffler hangers and rubber isolators. Loosen the two axle back to tailpipe retaining clamps. Remove each muffler from the car.

Slide your new muffler into the insulators, and slide your new clamp over the end of the axle back muffler, and attach it to the tailpipe loosely. Repeat this for the other side. Attach the bumper cover to the car. Remove the factory bolt from the mounting bracket.

Mark the center of the two holes on the new rear valance, on the center bumper cover mount. Drill two pilot holes with 1/8 inch drill bit, and finish up with a 1/4 inch drill bit. Install the supplied two J-clips. Install the supplied two eight millimeter bolts, and one factory bolt that you removed earlier.

Reinstall the two push pins you removed from the bumper cover mounts earlier, along with the supplied two eight millimeter bolts, and two nuts for the valence mount to the bumper cover mount. Align the tip in the rear valance opening. And tighten down your axle back to tailpipe clamp, as well as the tip to muffler clamp. Do this on the other side.

Now you can lower your car, finish installing the rear bumper cover, and reinstall your tail lights. And that little bit of work, ladies and gentleman, was well worth the effort. Because not only does this thing look awesome, it sounds mean. And if you follow the instructions, and take your time, you'll have no problem getting this rear valance and exhaust cap back kit on your car. Pick yours up at, and be sure to check out our full offering a Roush performance parts.

Roush Mustang Rear Valance Install (13-14) Tech Info

Ford Mustang - 2013 (13) - 2014 (14)