BMW M3 M4 G8X Carbon Fiber Rear Diffuser 2021-2023

Upgrade the rear-end appearance of your BMW G80 M3 or G82 M4 with this Carbon Fiber Rear Diffuser, designed to add a more aggressive and performance-focused finish to the G8X platform.

This rear diffuser enhances the quad exhaust area with a sharper lower bumper profile, helping the rear of the vehicle look wider, cleaner, and more refined. Its vehicle-specific design is shaped to complement the factory body lines of the M3 and M4.

Constructed from prepreg dry carbon fiber, this diffuser delivers a premium carbon fiber finish with carefully engineered aerodynamic styling and a bold rear-end presence.

Product Specifications

Key Features

• Designed for 2021-2023 BMW G80 M3 and G82 M4 models
• Carbon fiber rear diffuser adds a more aggressive lower rear-end appearance
• Frames the factory quad exhaust area for a sharper performance look
• Vehicle-specific design complements the G8X factory rear bumper lines
• Carefully engineered aero styling enhances the rear profile
• Made from prepreg dry carbon fiber for a premium finish
• Includes mounting tape and screws for installation
• Available in M3-specific and M4-specific dimensions for proper fitment

Configuration Options

• BMW G80 M3 rear diffuser configuration
• BMW G82 M4 rear diffuser configuration
• Prepreg dry carbon fiber finish

Package Includes

• One rear diffuser
• 3M tape
• Screws

Note: Professional installation is required. Please confirm whether your vehicle is an M3 or M4 before ordering, as dimensions vary by model.

Installation

• Rear diffuser installation
• Professional installation only
• Factory rear diffuser removal may be required
• Uses 3M tape and screws for mounting
• Test fit and align the diffuser before final installation
• Confirm exhaust clearance and rear bumper alignment before securing

Fitment

• 2021-2023 BMW M3 G80 Standard
• 2021-2023 BMW M3 G80 Competition
• 2021-2023 BMW M4 G82 Standard
• 2021-2023 BMW M4 G82 Competition
• 2023 BMW M4 CSL

United States: Free shipping available to the lower 48 states across all items. Other states will incur a shipping charge.

Worldwide: Free shipping is available for Complete Headlights, Taillights, DRLs. For custom headlight retrofits, carbon fiber products, and performance products, there will be a shipping charge.  

Please note:
• For Retrofits, you are purchasing a headlight modification service.
• If you select "Shipping own headlights to BayOptiks for modification", you are required to send us your headlights.
• If you choose "Purchase new OEM headlights", we will order and modify a new OEM headlight for you.
• Once your customizations are complete, we will ship it to you!

• Complete Headlights: 3-5 business days for order processing plus shipping time.
• Custom & Pre-Built Headlights: 6-8 weeks depending on the complexity and component availability.
• New OEM and cores: 6-8 weeks plus an additional 4-8 weeks as these are special orders base on the vehicle VIN due to different versions (North American, European, etc.)
• DRLs, Taillights, Brake Pads, and Carbon Fiber Aero: 3-5 business days for order processing, plus shipping time.
• Lens Replacements: 1-3 weeks plus shipping time.

Please note, we do not have control over the time frames of our vendors, manufacturers, and delivery services as they may delay processes in regards to components and shipment.