K2 Industries
Audi A4 B9 Avant Rear Diffuser Extension – Carbon Fiber
Check fitment before ordering
Match the year, make, model, trim and engine in the product details. Review mounting requirements and vehicle modifications. Ask us about this part.
Audi A4 B9 Avant Rear Diffuser Extension – Carbon Fiber
Sharpen the rear end of your Audi A4 B9 Avant with this carbon fiber rear diffuser extension. Molded to follow the factory bumper lines, it adds lower-end definition for a lower, wider visual stance and a more performance-inspired finish.
Build
- Material: Genuine carbon fiber, lightweight and structurally durable, with an authentic weave appearance over carbon-look alternatives
- Manufacturing: Precision-moulded for accurate bumper fitment
- Surface finish: High-polish gloss carbon black finish with a protective clear coat
- Configuration: Single-piece diffuser extension for the lower rear bumper
Design & Aerodynamics
- Aggressive stance: Diffuser extension adds depth to the lower rear for a lower, wider, more planted stance
- Carbon aesthetic: Gloss carbon black weave and high-polish finish create strong contrast against the factory paint
- Factory-style integration: Precision-molded to the contours of the factory rear bumper for a clean, seamless fit
Fitment
- Audi A4 B9 Avant (8W5)
- Fits the factory rear bumper only — not compatible with aftermarket bumper configurations
- Body style: Avant (wagon) only
- Confirm your model and trim against the product images before ordering
Package Contents
- 1 × carbon fiber rear diffuser extension
- Installation hardware (adhesive tape and/or mounting screws)
Installation
- Two mounting options: Fits using the supplied adhesive tape and/or mounting screws for a secure fit
- Drilling may be required: If you use the screw option, screw fixing pierces the bumper, so it is a permanent modification rather than a reversible fit
- Surface prep: If using adhesive tape, thoroughly clean, degrease, and dry the rear bumper before fitting to ensure maximum adhesion
- Alignment: Dry-fit and check the diffuser sits centred and even across the bumper before committing to either method
- Professional installation recommended for correct positioning, panel alignment, and a clean finish
Before You Install
- Confirm your car is an A4 B9 Avant before ordering — this is moulded for the Avant rear bumper
- Take care when parking rear-in — lower rear panels sit close to kerbs and parking blocks
- Adhesive installation is reversible, but removal and re-prep may be required if the diffuser needs repositioning
Your vehicle
Select a vehicle to check the supplied application records for this part.
Choose or change vehicle →Product reference & ordering help
Manufacturer & part identification
K2 Industries
| Option | SKU / part reference |
|---|---|
| Standard | 1576984590 |
Vehicle compatibility
Read the application years, model, trim, engine and exclusions in the description above. A make-level collection or product recommendation alone does not confirm fitment.
Request fitment help →Installation & specifications
Review the manufacturer’s specifications and installation notes above. Confirm required mounting hardware, tools and modifications before ordering. If instructions are not supplied, contact us with the part reference.
Shipping expectations
Processing and delivery vary by product, supplier and destination. Contact us to confirm timing for your part before planning an installation.
Shipping & delivery informationManufacturer warranty
Coverage and exclusions vary by manufacturer and part. Review the supplied product documentation or ask us for the applicable terms.
Warranty information