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Aeroflow Dynamics Rear Diffuser V4 (2015-2021 Subaru WRX/STI) - 1
Aeroflow Dynamics Rear Diffuser V4 (2015-2021 Subaru WRX/STI) - 2
Aeroflow Dynamics Rear Diffuser V4 (2015-2021 Subaru WRX/STI) - 3
Aeroflow Dynamics Rear Diffuser V4 (2015-2021 Subaru WRX/STI) - 4

Aeroflow Dynamics Rear Diffuser V4 (2015-2021 Subaru WRX/STI)

Special Order Item
Please see shipping policy for more info

AFD-VA-AL-DIFF-V4-GBK

Finish
Finish: Gloss jet black

Pairs well with
$ 799.98
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Designed for the 2015–2021 Subaru WRX / STI (Sedan)

🔧 Direct Fitment
Engineered for precise alignment with factory bumper points—no cutting or modification required.

🛠️ Material
Constructed from aerospace-grade lightweight aluminum to ensure strength, performance, and longevity.

⚙️ Finish & Build Quality
Professionally CNC-machined and powder coated in gloss black. Pre-drilled for a smooth installation process.

Made in USA
Proudly manufactured in the United States using high-grade materials and expert craftsmanship.

Production Lead Time
CNC items are made to order and have raw materials allocated to production once the order is placed. For concerns regarding current lead times, please review the CNC Products section in our Terms & Conditions.

🧰 Install-Friendly
Comes complete with all required hardware.
Professional installation is highly recommended.

💨 Why Add a Rear Diffuser to Your WRX/STI?
The V4 Rear Diffuser offers a bold, functional enhancement to your WRX or STI’s rear-end appearance. Its aggressive design helps manage airflow beneath the car to reduce drag and increase rear-end stability—giving your Subaru both show and go.

Confirmed Exhaust Fitments:

  • - Invidia R400
  • - Nameless Exhaust Systems
  • - Muffler Delete Setups
  • - Subiespeed Exhaust
  • - Militek Quadtip

Please email or call us if you have any questions regarding exhaust fitment.

Aeroflowdynamics Install Instructions

  • All Aeroflow Dynamic Exhaust are Built-to-Order with a lead time of 4-8 weeks. Once the order has been placed, it cannot be canceled.

No Returns for Aeroflow Dynamics Parts

All sales are final. We do not accept returns or exchanges, except in the case of a defective product. If you receive a defective product, please contact us within 2 days of receiving the product to arrange for a return or exchange.

To be eligible for a return or exchange due to a defective product, you must provide proof of purchase and the product must be in its original packaging.

We reserve the right to refuse any returns or exchanges that do not meet the above criteria.

If you have any questions or concerns about a product before making a purchase, please contact us for more information. We will be happy to assist you.

By making a purchase on our website, you acknowledge and agree to this no return policy

Aeroflowdynamics Return Policy

WARRANTY:

Warranty covers all defects in materials and craftsmanship over a 30-day period from purchase. Warranty is only applicable to the original purchaser/owner of the item(s). Warranty does not cover items damaged by customer misuse and or abuse. Aeroflowdynamics is NOT responsible for any and all damages caused by the improper installation of any product. Please mail sales@aeroflowdynamics.com with any questions in regards to warranty.

If the package arrived damaged, please notify us within 48 hours of when you receive the package. After the 48 hours, we will not be able to offer a refund or ship you a replacement.

Aeroflowdynamics Warranty

AEROFLOW DYNAMICS LOGO

AeroFlow Dyanmics

AeroFlow Dynamics is a California-based automotive parts company specializing in high-quality, precision-engineered aluminum aerodynamic upgrades such as splitters, wings, diffusers, fender flares, and overlays. Their products are CNC-machined from aerospace-grade aluminum, powder coated for durability, and proudly made in the USA with strict quality control. They offer components for a wide range of makes and models, including Subaru, Honda, Toyota, BMW, and more.

View More AeroFlow Dyanmics Products

Popular FAQs

Please read our FAQs page to find out more.

Why Should I Buy AeroFlow Dynamics Products from JD Customs USA?

Why Should I Buy AeroFlow Dynamics Products from JD Customs USA?

JD Customs USA is a trusted retailer for AeroFlow Dynamics aerodynamic components, offering enthusiasts a reliable place to purchase high-quality splitters, wings, diffusers, side skirts, and aero accessories. When you buy AeroFlow Dynamics products from JDC, you are working with a retailer that understands vehicle-specific aerodynamics, fitment accuracy, and the balance between performance and street-driven usability.

AeroFlow Dynamics is known for producing functional aero parts that combine aggressive styling with real-world aerodynamic benefits. JD Customs USA ensures these products are presented accurately and supported by a knowledgeable team that understands enthusiast builds.

Are AeroFlow Dynamics Products from JD Customs USA Authentic?

Yes. All AeroFlow Dynamics products sold by JD Customs USA are 100 percent authentic and sourced directly through authorized AeroFlow Dynamics distribution. This guarantees genuine materials, correct designs, and proper manufacturing standards.

Purchasing through JD Customs USA protects customers from imitation aero parts, incorrect replicas, or poorly fitting alternatives commonly found through unauthorized sellers.

Does JD Customs USA Help with AeroFlow Dynamics Fitment and Installation Questions?

Absolutely. Aerodynamic components require precise fitment and proper installation to perform correctly. JD Customs USA provides guidance to help customers confirm:

  • Vehicle compatibility and year ranges
  • Mounting requirements and hardware expectations
  • Differences between cosmetic aero and functional aero setups
  • Street, track, or show-oriented use cases

Our team helps ensure you choose the right AeroFlow Dynamics components for your goals before placing an order.

Why Buy AeroFlow Dynamics from JD Customs USA Instead of Other Retailers?

Many online retailers list aero parts with limited detail or unrealistic expectations. JD Customs USA provides accurate product descriptions, clear installation notes, and honest guidance, helping customers understand exactly what they are purchasing.

We also emphasize transparency regarding drilling requirements, adjustability, and real-world usage so there are no surprises during installation.

What Makes JD Customs USA the Right Place to Buy AeroFlow Dynamics Products?

JD Customs USA is an enthusiast-driven retailer focused on quality, transparency, and long-term customer satisfaction. We curate AeroFlow Dynamics products that meet our standards for design, durability, and functional performance.

When you purchase AeroFlow Dynamics products from JD Customs USA, you receive:

  • Genuine AeroFlow Dynamics aerodynamic components
  • Verified vehicle fitment and accurate product listings
  • Clear expectations for installation and use
  • Support from knowledgeable automotive enthusiasts
  • Secure checkout and careful order handling

Choosing JD Customs USA ensures you are investing in authentic AeroFlow Dynamics aero products with the expertise and support needed to complete your build confidently and correctly.