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Black Oval Automotive
2013-2014 Roush Mustang - Rear Side Splitter Kit — image 1

Aero & Body

2013-2014 Roush Mustang - Rear Side Splitter Kit

Roush part # 421405

$149.99

Roush retail price · part only

Installed at our shop

est. $299.99

Part $149.99 + about 1 hr labor at $150/hr ($150.00).

Estimate only — shop supplies and sales tax not included. We confirm the final installed price for your exact vehicle before any work.

Fits: 2013–2014 Mustang

Installed at our East Bridgewater shop, or shipped anywhere in the US. Prefer to talk? 508-715-3554

  • Genuine ROUSH Performance part, from an authorized Gold Dealer
  • Installed by Ford specialists at our East Bridgewater shop
  • Roush retail price. Installed price estimated up front, confirmed before work

Prices and availability subject to change. Prices updated October 2, 2026.

Details & specs

Elevate the appearance of your 2013-2014 Ford Mustang with the Roush Rear Side Splitter Kit, designed to create a bold and aggressive styling line between the sides of your vehicle and the road.

This kit includes both the left and right side splitters, perfectly complementing the Roush side rocker splitters (Part # 420092). It's a great addition for all 2013-2014 Mustangs, including the GT, GT500, V6, Boss 302, and California Special models.

Crafted from high-strength TPO (Thermoplastic Poly Olefin), these splitters are built to last and withstand the rigors of the road. Using a high-pressure injection molding process, the same method employed by automotive manufacturers, ensures excellent impact resistance while remaining tough yet flexible. The splitters come unpainted, featuring a black stipple finish that enhances durability against rock impacts during your drives.

Installation is a breeze, taking less than an hour, and there's no need for trimming, making it even more convenient than competitor products. The kit includes all the necessary hardware, templates, and detailed instructions to simplify the process.

Roush's Rear Side Splitter Kit is designed with precision, using OEM CAD data to ensure a precise fit that aligns seamlessly with your Mustang's rear valance. Plus, Roush stands behind this product with a 90-Day Limited Parts Warranty for your peace of mind.

Embrace true race-inspired styling with this kit, enhancing your Mustang's appearance while maintaining the highest standards of quality and longevity. Roush's dedication to performance and style shines through in every part they offer. Don't miss out on the opportunity to upgrade your 2013-2014 Ford Mustang with the Roush Rear Side Splitter Kit!

More Roush parts for your Mustang

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