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How to install a Roush Side Rocker Panel Splitters on your 2010-2012 Mustang

Installation Time

2 hours

Tools Required
  • Isopropyl Alcohol
  • Pliers
  • Drill
  • 1/4" Drill Bit
  • Phillips Screw Driver
  • Soft Lint-Free Cloth
  • Electrical Tape
  • 3M™ General Purpose Adhesive Cleaner (PN 08984) or 3M™ Prep Solvent 70 Low VOC Cleaner (PN 08973) (Optional)
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Shop Parts in this Guide


USE EXTREME CAUTION WHEN WORKING UNDERNEATH VEHICLE. Never get near or underneath vehicle until you are confident that it is safely supported and will not move or fall from its raised position.



The information contained in this publication was accurate and in effect at the time the publication was approved for printing and is subject to change without notice or liability. ROUSH Performance Products (RPP) reserves the right to revise the information presented herein or to discontinue the production of parts described at any time.




Appropriate disassembly, assembly methods and procedures are essential to ensure the personal safety of the individual performing the kit installation. Improper installation due to the failure to correctly follow these instructions could cause personal injury or death. Read each step of the installation manual carefully before starting the actual installation.

Therefore, do not allow flames, sparks or flammable substances to come near the battery.

1. Always wear safety glasses for eye protection.

2. Place ignition switch in the OFF position.

3. Always apply the parking brake when working on a vehicle.

4. Chock the front and rear tires to prevent unexpected vehicle movement.

5. If working without a lift, always consult vehicle manual for correct lifting specifications.

6. Operate the engine only in well-ventilated areas to avoid exposure to carbon monoxide.

7. Do not smoke or use flammable items near or around the fuel system.

8. Use chemicals and cleaners in well-ventilated areas.

9. Batteries produce explosive gases, which can cause personal injury.

10. Keeps hands and any other objects away from the radiator fan blades.

11. Keep yourself and your clothing away from moving parts when the engine is running.

12. Do not wear loose clothing or jewelry that can get caught in rotating parts or scratch surface finishes.

13. Allow the engine, cooling system, brakes and exhaust to cool before working on a vehicle.


Perform this installation on a good clean level surface for maximum safety and with the engine turned off.


1. Select the LH ROUSH Rocker Splitter. The LH and RH Rocker Splitters are marked on the back side near the center of the part. Refer to Figures 1.

Figures 1

2. With an assistant, hold the left ROUSH Rocker Splitter in position and visually note where the foam tape is to adhere to the factory rocker panel molding. Refer to Figure 2. Remove the Rocker Splitter.

Figure 2

3. Clean the noted area and apply the 3M™ 4298 Adhesion Promoter to the factory rocker panel molding. Refer to the 3M™ Technical Data Sheet, included, for prep and application procedures.

4. Using a pair of pliers, reach into the rocker panel molding pockets as shown and pull the eight (8) push pins from the left side rocker panel molding and discard. Refer to Figures 3. The rocker panel molding will remain in place with the upper fasteners retaining it to the body.

(One push pin shown, all others are similar) Figures 3

5. Prepare the Rocker Splitter for installation by bending and creasing the tape pull tabs as shown in Figure 4. Do not expose or touch the foam tape.

Figure 4

6. Loosely install the left side Rocker Splitter and eight (8) new Push Pins. Ensure that the foam tape pull tabs are accessible. Refer to Figure 5. The picture shows a large gap for clarity. Press the Push Pins in, leaving a 1/8” to 1/4” gap.

Figure 5

7. Starting at the front and ensuring that the factory rocker panel molding is nested into the recessed feature in the Rocker Splitter (Refer to Figures 6), fully insert the eight (8) Push Pins. The handle of a screw driver works well to fully press the Push Pins in.

Figure 6

8. Pull the four (4) tape pull tabs to remove the tape backing. Refer to Figure 7.

Figure 7

9. Press the left side Rocker Splitter into place. Apply firm pressure at 3-4 inch intervals along the entire length of the Rocker Splitter to ensure a strong bond.

10. Using the installed left side Rocker Splitter as a template, drill five (5) 1/4” holes into the factory rocker panel molding as shown in Figures 8.

Assembly Tip: Place several wraps of electrical tape 1” from the tip of the drill bit to act as a drill stop. Refer to Figures 8.

(Rear hole shown, others are similar) Figures 8

11. Install a new Push Pin into each of the five (5) drilled holes. Refer to Figures 9.

(Three of five Push Pins shown.) Figures 9

12. Repeat steps 1 - 11 for the right side Rocker Splitter.

Congratulations!!! You have completed the installation of the ROUSH Performance Products, Rocker Splitter Kit. It is recommended that you save all parts removed from your vehicle during the installation of this kit.

This guide applies to Vehicle years: 2010, 2011, 2012, 2013, 2014 and Submodels: Boss 302, V6, GT, GT500