18-23 Mustang Rear Diffuser/Splitter Combo

Complete the aerodynamic profile of the S550 with a full rear-end kit designed for presence and durability. Specifically engineered for the 2018–2023 Mustang, this package includes both the center rear diffuser and matching rear side splitters (spats) to provide a wider, track-ready stance.

The ACM Advantage

While standard market options often utilize thin plastic, these components are constructed from 6mm Premium Aluminum Composite Material (ACM). This heavy-duty, three-layer sandwich consists of two sheets of aluminum bonded to a solid core, providing double the thickness and significantly more rigidity than industry standards.

• Heavy-Duty Construction: The 6mm thickness ensures zero warping, even under high-speed air pressure or extreme exhaust heat.

• Impact Resistant: Engineered to withstand road debris without cracking, offering a major durability upgrade over brittle ABS plastic.

• 100% Rust-Proof: The aluminum faces and composite core are completely impervious to the elements.

• Satin Black Finish: Pre-finished in a sleek black that matches factory trim perfectly.

Key Features

• Full Rear Kit: Includes the center diffuser and two rear side splitters for a seamless, "wrapped" look.

• Adjustable Depth: The center section features built-in adjustability, allowing for a custom recessed or extended fitment to match specific style preferences.

• Precision Fit: Contoured to flow with the 2018+ rear valence for an integrated, high-end appearance.

Streamlined Installation

This kit is designed with the DIY enthusiast in mind. There is no requirement for complex brackets or bumper removal.

• Simple Mounting: Installs quickly using provided self-tapping screws directly into the bottom of the factory rear valence/bumper.

• Pre-Assembled: Components ship fully pre-assembled. Simply align, secure, and the installation is complete.

Installation & Compatibility

Pro Tip: Because this kit includes adjustability, it is recommended to mock up the center section with clamps first to determine the desired extension before fully securing the unit.

18-23 Rear Diffuser Combo Installation Guide