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Audi A4 B9 Avant (2017-2019) Carbon Fiber Diffuser – Performance Diffuser Extension

Audi A4 B9 Avant (2017-2019) Carbon Fiber Diffuser – Performance Diffuser Extension

SKU: 1576984590

Sale price  $579.99 USD Regular price  $636.00 USD
Shipping calculated at checkout.

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

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