Scopione carbon fiber rear bumper diffuser for Audi A4 B9 2016–2019 S-Line dual exhaust
Bottom-facing view of Scopione carbon fiber rear diffuser for Audi A4 B9 dual exhaust
Close-up of carbon fiber weave on Scopione Audi A4 B9 rear bumper diffuser
Angled view of Scopione carbon fiber rear diffuser for Audi A4 B9 dual exhaust
Underside view of Scopione carbon fiber rear diffuser for Audi A4 B9 S-Line
Scopione carbon fiber rear diffuser installed on Audi A4 B9 S-Line with dual exhaust

Carbon Fiber Rear Bumper Diffuser for Audi 17-19 A4 B9 – 8W

Rated 5.00 out of 5 based on 14 customer ratings
(14 Reviews)

Original price was: $750.00.Current price is: $400.00.

Part(s) Fitment:
  • Make: for Audi
  • Model: for A4 B9
  • Year(s): 2017-2019
  • **FITS ONLY: Basic Trim Models
  • **Will NOT Fit: Singe or Quad Exhausts
Part(s) Features:
  • ✔ Real Carbon Fiber – 2×2 3K Twill Weave with a Glossy Finish.
  • ✔ Direct Replacement – Designed as a Replacement part.
  • ✔ UV & Element-Resistant Coating – Protects against fading and discoloration.
  • ✔ Easy Maintenance – Simple to clean using everyday cleaning methods.
  • ✔ Quick & Hassle-Free Installation – No modifications required.
  • ✔ Distinctive Styling Upgrade – Enhances aesthetics with an aggressive, high-performance look.
  • ✔ Limited Warranty: 1 Year (365 days).

**Note: Please compare your vehicle parts to Scopione Images

In stock

In-Stock & Ready to Ship (Fast Dispatch)

Ships from US Locations (No Overseas Delays)

Insured Shipping + Careful Packaging (Safe)

SKU: SC-AU-A4B9-DIFF-CFG-CA08 Category: Tag: Brand:
100% Carbon Fiber2x2 3K Twill WeaveDirect ReplacementNo Hardware Included12 Months Limited Warranty

Carbon Fiber Rear Bumper Replacement Diffuser Valance by Scopione for Audi 2017-2019 A4 B9 – 8W – Avants & Saloons

Take your Audi A4 B9 (2017–2019) to the next level with the Scopione Carbon Fiber Rear Bumper Diffuser—designed to enhance rear-end styling, improve airflow, and deliver that aggressive S4-style carbon fiber look. Precision-engineered for perfect OEM-style fitment, this lightweight diffuser offers the ultimate blend of performance and appearance.

Key Features:

  • Real Carbon Fiber Construction – Crafted from high-grade lightweight carbon fiber with a glossy UV-resistant finish that withstands heat, weather, and road wear.
  • Aggressive Styling & Aerodynamics – Designed to improve airflow under the car while giving your Audi A4 B9 rear bumper a more dynamic, race-inspired look.
  • S-Line & S4-Inspired Fitment – Compatible with Audi A4 B9 (8W5, 8WD) and other B9 models (8W2, 8WC), including sedan and Avant. Dual exhaust outlet design matches sporty factory aesthetics or aftermarket setups.
  • Easy Installation – Direct replacement for factory rear diffuser—no cutting or major modification required. Mounts using OEM tabs and fasteners.
  • Scopione Signature Quality – Engineered with Scopione’s commitment to premium exterior styling, fitment precision, and durable construction.

Replacement Diffuser Valance Fits Models Below – This Will Replace Original Diffuser ONLY

  • Audi A4 B9 8W: 2017, 2018, 2019 – Please make sure your OEM Diffuser as shown in the Images

Why Choose Our A4 B9 Carbon Fiber Diffuser?

Whether you’re going for a subtle exterior upgrade or building a full Audi A4 B9 carbon fiber body kit, the Scopione carbon fiber rear diffuser is the perfect finishing touch. Get show-car looks with street-ready durability and precision fitment trusted by Audi enthusiasts worldwide.

Installation:
  • Parts are hand made to replace Factory Diffuser
  • No modifications are needed
  • Professional Installation is advised
  • Parts are designed specifically for your make and model
  • Secured in place with place holders/clips
Scopione Package Contents:
  • ( 1 ) One Packaging Box
  • ( 1 ) Replacement Rear Diffuser
  • ( 0 ) Installation Manual, Tools or Hardware are NOT Included

Enhance your Audi A4’s rear bumper today with this high-quality carbon fiber diffuser – the ultimate blend of performance, protection, and aesthetics for your machine. Give your Audi the aggressive look it deserves – choose Scopione for performance, precision, and premium style.

**Note: if for any reason you decide over time that you want to remove Scopione part(s), the process can be reversed.

Interchange Part Numbers for RHD and LHD models: 8W0.807.521.A, 8W0807521A, 8W0807521A9B9

Installation guidance for Scopione replacement and add-on parts. For best results, test-fit before any paintwork, drilling, trimming, or permanent installation. If you would like us to confirm compatibility or your installation approach before you begin, contact us with clear photos of your OEM part and any relevant options.

Quick install overview
  • Unbox & inspect: confirm the part, finish, and contents before starting. Keep all packaging until installation is complete.
  • Dry test-fit first: verify alignment, gaps, and clearance before any drilling, trimming, paintwork, or permanent mounting.
  • Replacement parts: typically use OEM mounting points and may reuse factory hardware—tighten evenly and avoid over-torquing carbon.
  • Add-on parts: may install with 3M VHB tape, brackets, or light trimming depending on your setup and existing modifications.
  • Protect the finish: use clean microfiber towels and masking tape on edges while positioning and aligning.
  • Professional installation recommended: especially for aero components and precision-fit parts.
Before you start

Work on a clean, well-lit surface. Confirm left/right orientation, compare the part to your OEM component, and verify that mounting points and edges align during a dry-fit. If your vehicle has aftermarket bumpers/diffusers, previous repairs, or custom bodywork, fitment may vary—do not force alignment before checking the install position.

Dry-fit & alignment tips

Position the part gently and never force it into place. If fasteners are used, hand-start them first, then check gaps, edge alignment, and clearance before tightening evenly. Use low-tack tape to mark reference points so you can repeat the exact placement after cleaning or adhesive preparation.

Adhesive installs (3M tape)

Prep is everything. Clean both surfaces with isopropyl alcohol, make sure they are fully dry, and install in a warm environment whenever possible. Apply firm, even pressure along the entire tape line to ensure full contact. For best adhesion, avoid washing or rain exposure immediately after installation and allow adequate cure time before heavy use.

Fastener installs (bolts/screws/clips)

Hand-start all fasteners to prevent cross-threading, then tighten gradually and evenly to keep the part aligned. Do not over-tighten—carbon fiber can crack from excessive point load. When possible, follow OEM torque guidance for that mounting location and use washers/spacers as appropriate to distribute pressure.

Installation details
  • Details: Installation specifics depend on the part. Review the Part Details and Features tabs for guidance, or contact us for confirmation before you begin.
Suggested tools & supplies

In most cases you’ll want basic hand tools, trim tools, clean microfiber towels, isopropyl alcohol, and masking tape. If using 3M tape, gentle warming (heat gun on low or a warm environment) helps improve initial adhesion. Exact tools and supplies vary by part and vehicle setup.

Important note on modifications

Only drill, trim, or perform paintwork after a successful dry test-fit and confirmed alignment. If anything looks off, stop before making permanent changes and contact us—we’ll help you verify the correct placement and approach.

After-install checklist

Verify clearance and movement (full steering lock where applicable), confirm there is no contact with heat sources, and ensure all edges are seated securely. If installed with fasteners, re-check alignment and tightness after initial use to account for settling and vibration.

Care & maintenance

Cleaning: Use a pH-neutral car shampoo and clean microfiber towels.

Avoid: harsh solvents (acetone, brake cleaner), abrasive pads, aggressive cutting compounds, and pressure-washing directly at edges/seams.

Protection: Treat the finish like painted bodywork. A quality sealant or ceramic coating may be used if compatible with your detailer’s process.

For long-term gloss and UV protection, many owners choose a quality sealant or ceramic coating applied by a professional detailer. If you want recommendations for safe products for your finish or climate, contact us and we’ll help.

If something doesn’t line up

Stop before forcing, drilling, trimming, or making any permanent changes. Misalignment is often caused by aftermarket bumpers/diffusers, prior repairs/bodywork, or positioning during the dry-fit. Send clear photos of the mounting points, the surrounding area, and a wider shot of the overall fitment, and we’ll help you troubleshoot the correct placement and next step.

Need tracking or delivery help?

You can view shipment updates on our Order Tracking page. If you need assistance, contact us with your order number and (if applicable) photos of the box/label, and we’ll help resolve it quickly.

Need help before installing? Contact us
with clear photos of your OEM part and we’ll guide you.

Quick answers on fitment, finish, shipping, and warranty. If you’re unsure about compatibility, message us with clear photos of your OEM part (and any relevant options) and we’ll help confirm fitment.

Will this fit my vehicle?

Start with the Compatibility tab on this page. Fitment can vary by factory options, model-year changes, and aftermarket bumpers/diffusers. If you’d like a quick confirmation before ordering, send clear photos of your OEM part (and any relevant options) and we’ll help verify compatibility.

What warranty do you offer?

Most products include a 6–12 month limited warranty against manufacturing defects (coverage varies by item). To protect coverage, please test-fit before any cutting, drilling, paintwork, or permanent installation. Warranty does not cover damage caused by improper installation, accidents/impact, road debris, or harsh chemicals/cleaners.

Do your carbon-fiber parts look exactly like the photos?

Carbon fiber is hand-laid, so subtle variations in weave direction, pattern alignment, and gloss can occur—this is normal and part of the material’s character. Every piece is inspected for finish quality before it ships.

Is installation hardware included?

Hardware inclusion varies by product. If hardware is not listed in the product details, the part is typically designed to reuse OEM mounting points and factory fasteners. For best results—and to protect the finish—professional installation is recommended.

Do parts come painted, and can I paint carbon fiber?

Most carbon-fiber parts arrive with a clear-coated finish unless otherwise stated. You can leave the carbon exposed, wrap it, or paint it for a matched look. For best results, test-fit before any paintwork and follow your installer/body shop’s prep process for proper adhesion.

When will my order ship and how do I track it?

In-stock items typically ship within 2–3 business days. If an item is made-to-order or temporarily out of stock, we’ll contact you with the expected lead time. Once your order ships, tracking is emailed automatically and you can also check updates on our Order Tracking page.

How are parts packaged, and what if there is shipping damage?

Every part is carefully packed to protect the finish in transit and shipped in a plain outer carton. Please inspect your delivery upon arrival. If anything looks damaged or missing, take clear photos of the outer box, shipping label, packing materials, and the item, then contact us within 48 hours so we can resolve it as quickly as possible.

Do you ship internationally?

Yes, we ship internationally. Available shipping options and rates are shown at checkout based on your destination and package size. Import duties, taxes, and any broker/clearance fees (if applicable) are determined by your country and are the buyer’s responsibility.

Can I cancel or change my order after purchase?

If you need to change or cancel an order, please contact us as soon as possible. If the order has not shipped, we’ll do our best to accommodate your request. Once an order is in processing or has shipped, changes may be limited.

How do I care for carbon fiber?

Treat carbon fiber like painted bodywork: wash with a pH-neutral car shampoo, rinse thoroughly, and dry with clean microfiber towels. Avoid harsh solvents, abrasive pads, and aggressive cutting compounds. If you’re unsure what’s safe for your finish or climate (UV/heat), message us and we’ll advise.

Please Note: Products sold by Scopione are intended for lawful use only. Scopione is not affiliated with or endorsed by any vehicle manufacturer.
All logos, names, and images shown are used for nominative and informational purposes.

Still have questions? Contact us

14 reviews for Carbon Fiber Rear Bumper Diffuser for Audi 17-19 A4 B9 – 8W

  1. Rated 5 out of 5

    Jason L. –

    Scopione’s Diffuser Made My Audi A4 B9 Look Like a Different Car – After adding the Scopione carbon fiber rear diffuser to my 2017 Audi A4 B9 S-Line, the entire rear end looks sharper and more aggressive. The diffuser completely changes the vibe from stock to sporty. The fitment was precise, lining up with all OEM mounting points, and I didn’t need to modify anything.

    The carbon fiber quality is top-notch—deep gloss, tight weave, and it matches perfectly with my other carbon accents. If you’re looking for a dual exhaust carbon fiber upgrade that’s functional and stunning, this is the one. Scopione really delivered a high-end product that transforms the car visually and aerodynamically.

  2. Rated 5 out of 5

    Michael D. –

    Best Carbon Fiber Exterior Mod for the B9 A4 – Out of all the carbon fiber exterior parts for the Audi A4 B9, this rear diffuser is the most impactful. It’s lightweight, looks amazing, and fits bumpers with zero hassle. Scopione nailed the design and finish.

  3. Rated 5 out of 5

    Kevin R. –

    Transforms the Rear View in Minutes – Install took less than 30 minutes, and the transformation was huge. The Scopione carbon fiber rear diffuser gave my 2018 Audi A4 B9 a bold, aggressive finish that finally matches the rest of my build.

  4. Rated 5 out of 5

    Luis M. –

    Excellent Quality, Real Carbon, No Gimmicks – Unlike other brands, Scopione uses real carbon fiber, not overlay junk. This Audi A4 B9 diffuser feels solid and looks incredible installed. You get high-end style and functionality with perfect OEM compatibility.

  5. Rated 5 out of 5

    Trevor G. –

    Excellent Upgrade That Blends Performance and Style – I’ve been modifying my 2018 Audi A4 B9 2.0T Quattro, and this Scopione rear bumper diffuser has been the best exterior mod so far. The carbon fiber is real—not overlay—and it’s lightweight, durable, and perfectly molded. You can tell this is made by a brand that cares about fit and finish. The dual outlet design worked great with my aftermarket exhaust. I’ve noticed cleaner lines and a rear profile that finally looks as performance-focused as the rest of the car. Scopione gets 5 stars from me.

  6. Rated 5 out of 5

    Dylan V. –

    Made My A4 Look Like an S4 – The Scopione rear diffuser gave my 2019 A4 B9 that S4 carbon rear valance look without the price tag of a full conversion. It lines up perfectly and brings the rear bumper to life. Super happy with the upgrade.

  7. Rated 5 out of 5

    Isaiah K. –

    Track-Ready Look, Street-Ready Fitment – this Audi A4 B9 carbon fiber diffuser added a race-inspired finish to the rear of my 2017 A4. I didn’t have to drill anything—it just clipped into the stock tabs. Lightweight, clean, and fits like a glove.

  8. Rated 5 out of 5

    Brandon T. –

    Truly OEM+ Quality – Worth Every Dollar

    This carbon fiber rear diffuser for Audi A4 B9 is easily one of the best investments I’ve made in my car. The install was smooth—it snapped right into place using the original mounting points. What I love most is how the design enhances the stock rear bumper without overdoing it.

    The Scopione diffuser has that aggressive edge I wanted while keeping everything clean and balanced. It feels like something Audi could have offered as part of a factory sport package. You get the S4-style diffuser look with premium aftermarket quality.

  9. Rated 5 out of 5

    Gabriel C. –

    Looks Amazing, Fits Even Better

    The hardest part of customizing my 2019 Audi A4 B9 S-Line has been finding parts that actually fit. This Scopione carbon fiber diffuser fit perfectly right out of the box. No gaps, no drilling, and it aligned beautifully with the dual exhaust cutouts.

    The finish is deep and glossy, and it really ties the whole rear end together with my side skirts and spoiler. If you’re building a clean, carbon-themed exterior, this piece is essential. Bonus: Scopione shipped fast and packed it extremely well.

  10. Rated 5 out of 5

    Jared P. –

    Aggressive Look Without Losing OEM Fitment – The Scopione carbon fiber rear diffuser completely changed the rear-end look of my 2018 Audi A4 B9. The fitment was spot-on—no trimming or gaps—and the gloss carbon finish perfectly matched my other carbon accents. It looks like it came from the factory!

  11. Rated 5 out of 5

    Troy S. –

    Perfect Carbon Upgrade for Audi A4 B9 – I’ve been slowly customizing my 2017 Audi A4 B9 2.0T, and this Scopione rear diffuser gave me the S4-style rear end I’ve always wanted. The dual exhaust cutouts line up perfectly, and it really adds a sportier, more aggressive look. Total game-changer.

  12. Rated 5 out of 5

    Adrian N. –

    Premium Carbon Fiber and Real Performance Styling – This isn’t just for looks. The Scopione Audi A4 B9 carbon fiber rear diffuser actually improved airflow and made my rear bumper feel more complete. The carbon is real, lightweight, and holds up great under weather and heat. Highly recommend it for any B9 owner looking to elevate their build.

  13. Rated 5 out of 5

    Cody H. –

    Scopione Delivers Yet Again – 10/10 – I’ve bought carbon parts from Scopione before and this rear bumper diffuser for the Audi B9 is top-tier like everything else they make. The carbon fiber weave is flawless, installation was easy, and the dual outlet design makes it perfect for performance exhaust setups.

  14. Rated 5 out of 5

    Shane W. –

    Subtle But Aggressive – A Must for Any A4 B9 Build – I didn’t want anything too flashy, just a clean and performance-oriented diffuser for my 2019 Audi A4 B9. The Scopione rear carbon fiber diffuser was exactly what I was looking for. It adds depth to the rear bumper, works with the factory exhaust, and provides a subtle yet aggressive upgrade. It’s also incredibly light and made from real carbon—not fake wrap or ABS plastic. The install was easy, and the diffuser lines up with the OEM bumper flawlessly. Highly recommend it to anyone doing a B9 S-Line style exterior customization.

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Scopione is designed for enthusiasts who expect precise fitment, a high-quality finish, and a premium buying experience. Here is what you can count on when you choose Scopione carbon-fiber products.

Fitment confidence
  • Compatibility-first: start with the Compatibility tab for the most accurate fitment notes.
  • Pre-purchase support: if anything is unclear, send clear photos of your OEM part and we’ll help verify compatibility.
  • Installer-friendly process: we recommend a dry test-fit before any paintwork or permanent modifications.
Premium finish standards

Carbon fiber is hand-laid, so subtle variations in weave direction, pattern alignment, and gloss can occur—this is normal and part of the material. Every piece is inspected for overall finish quality before it ships.

Premium ownership experience
  • Protected shipping: parts are carefully packed to help protect the finish in transit and shipped in a plain outer carton.
  • Fast resolution: if anything arrives damaged or missing, contact us within 48 hours with clear photos and we’ll assist promptly.
  • Warranty clarity: most products include a 6–12 month limited warranty against manufacturing defects (coverage varies by item).
Care & maintenance guidance

We provide clear care guidance so your carbon fiber stays looking its best: wash with a pH-neutral car shampoo, dry with clean microfiber towels, and avoid harsh solvents or abrasive pads.

Please Note: Products sold by Scopione are intended for lawful use only. Scopione is not affiliated with or endorsed by any vehicle manufacturer.
All logos, names, and images shown are used for nominative and informational purposes.

Still have questions? Contact us
Weight 5 lbs
Dimensions 54 × 10 × 10 in
Condition

New
Surface Finish

Glossy Black
Condition New

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