Audi S4 rear view with premium carbon fiber diffuser installed
Close-up of carbon fiber rear diffuser texture on Audi A4 S Line
Side angle of Audi S4 showing carbon fiber rear diffuser design
Sporty carbon fiber rear diffuser enhancing Audi A4 S Line styling
High-performance carbon fiber rear diffuser for Audi S4 sedan
Audi A4 S Line rear diffuser made from durable carbon fiber
Aggressive rear bumper look with carbon fiber diffuser for Audi S4
Lightweight carbon fiber rear diffuser improving aerodynamics
Premium quality carbon fiber rear diffuser for Audi S4 & A4 S Line
Audi rear diffuser upgrade in carbon fiber by Ausen Performance
Audi S4 rear view with premium carbon fiber diffuser installed
Close-up of carbon fiber rear diffuser texture on Audi A4 S Line
Side angle of Audi S4 showing carbon fiber rear diffuser design
Sporty carbon fiber rear diffuser enhancing Audi A4 S Line styling
High-performance carbon fiber rear diffuser for Audi S4 sedan
Audi A4 S Line rear diffuser made from durable carbon fiber
Aggressive rear bumper look with carbon fiber diffuser for Audi S4
Lightweight carbon fiber rear diffuser improving aerodynamics
Premium quality carbon fiber rear diffuser for Audi S4 & A4 S Line
Audi rear diffuser upgrade in carbon fiber by Ausen Performance

Upgrade Your Audi S4 / A4 S Line with a Premium Carbon Fiber Rear Diffuser

Enhance the style and performance of your Audi S4 / A4 S Line with the premium carbon fiber rear diffuser by Ausen Performance. Crafted from high-quality carbon fiber, this diffuser is engineered for precision fitment, lightweight strength, and long-lasting durability.

The sleek and aggressive design of this carbon fiber rear diffuser adds a sporty and luxurious touch to your vehicle’s rear end, making it stand out on the road. Its lightweight construction minimizes added weight while ensuring robust performance and resistance to wear, providing both aesthetic appeal and functional reliability.

Designed to improve aerodynamics, this carbon fiber rear diffuser reduces drag and enhances stability at high speeds. Its precise contours optimize airflow under the car, promoting better handling and a smoother driving experience.

Installation is simple and hassle-free. The carbon fiber rear diffuser comes with all necessary hardware and is designed for seamless integration with your factory bumper for a professional, custom look.

Elevate your Audi S4 / A4 S Line with this premium carbon fiber rear diffuser from Ausen Performance—where style, performance, and craftsmanship meet.

Product Details:

  • Custom-made to order: Production 1-3 weeks, Delivery 1-2 weeks

  • Fitment: 2020–2021 Audi S4 / A4 S Line Sedan

  • Note: Custom-made products cannot be exchanged or returned

Premium Carbon Fiber Construction
Expertly crafted from high-quality carbon fiber, this rear diffuser offers exceptional strength, lightweight performance, and long-lasting durability for your Audi S4 or A4 S Line.

Aggressive Sport-Inspired Design
Designed to enhance the rear-end aesthetics, this diffuser gives your vehicle a race-ready appearance with a more dynamic and aggressive stance.

Aerodynamic Performance
Engineered to optimize airflow, this diffuser improves aerodynamics by reducing drag and increasing rear downforce for better stability and handling at high speeds.

UV-Resistant Gloss Finish
Featuring a high-gloss UV-resistant coating, this diffuser maintains its deep carbon fiber shine while protecting against fading, yellowing, and environmental damage.

Precision Fitment
Designed specifically for the Audi S4 and A4 S Line, this diffuser ensures a seamless OEM-like fit, integrating flawlessly with the factory bumper for a clean, professional look.

Easy Installation
This rear diffuser is designed for a hassle-free installation, utilizing factory mounting points for a secure fit with minimal modifications required.

1 unit of the Carbon Fiber Rear Diffuser + 3M and necessary screws for ease of installation.

Carbon Fiber Rear Diffuser - Audi S4 / A4 S Line

$2,169.99 $2,489.99
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Upgrade Your Audi S4 / A4 S Line with a Premium Carbon Fiber Rear Diffuser

Enhance the style and performance of your Audi S4 / A4 S Line with the premium carbon fiber rear diffuser by Ausen Performance. Crafted from high-quality carbon fiber, this diffuser is engineered for precision fitment, lightweight strength, and long-lasting durability.

The sleek and aggressive design of this carbon fiber rear diffuser adds a sporty and luxurious touch to your vehicle’s rear end, making it stand out on the road. Its lightweight construction minimizes added weight while ensuring robust performance and resistance to wear, providing both aesthetic appeal and functional reliability.

Designed to improve aerodynamics, this carbon fiber rear diffuser reduces drag and enhances stability at high speeds. Its precise contours optimize airflow under the car, promoting better handling and a smoother driving experience.

Installation is simple and hassle-free. The carbon fiber rear diffuser comes with all necessary hardware and is designed for seamless integration with your factory bumper for a professional, custom look.

Elevate your Audi S4 / A4 S Line with this premium carbon fiber rear diffuser from Ausen Performance—where style, performance, and craftsmanship meet.

Product Details:

  • Custom-made to order: Production 1-3 weeks, Delivery 1-2 weeks

  • Fitment: 2020–2021 Audi S4 / A4 S Line Sedan

  • Note: Custom-made products cannot be exchanged or returned

Premium Carbon Fiber Construction
Expertly crafted from high-quality carbon fiber, this rear diffuser offers exceptional strength, lightweight performance, and long-lasting durability for your Audi S4 or A4 S Line.

Aggressive Sport-Inspired Design
Designed to enhance the rear-end aesthetics, this diffuser gives your vehicle a race-ready appearance with a more dynamic and aggressive stance.

Aerodynamic Performance
Engineered to optimize airflow, this diffuser improves aerodynamics by reducing drag and increasing rear downforce for better stability and handling at high speeds.

UV-Resistant Gloss Finish
Featuring a high-gloss UV-resistant coating, this diffuser maintains its deep carbon fiber shine while protecting against fading, yellowing, and environmental damage.

Precision Fitment
Designed specifically for the Audi S4 and A4 S Line, this diffuser ensures a seamless OEM-like fit, integrating flawlessly with the factory bumper for a clean, professional look.

Easy Installation
This rear diffuser is designed for a hassle-free installation, utilizing factory mounting points for a secure fit with minimal modifications required.

1 unit of the Carbon Fiber Rear Diffuser + 3M and necessary screws for ease of installation.

Upgrade Your Audi S4 / A4 S Line with a Premium Carbon Fiber Rear Diffuser

Enhance the style and performance of your Audi S4 / A4 S Line with the premium carbon fiber rear diffuser by Ausen Performance. Crafted from high-quality carbon fiber, this diffuser is engineered for precision fitment, lightweight strength, and long-lasting durability.

The sleek and aggressive design of this carbon fiber rear diffuser adds a sporty and luxurious touch to your vehicle’s rear end, making it stand out on the road. Its lightweight construction minimizes added weight while ensuring robust performance and resistance to wear, providing both aesthetic appeal and functional reliability.

Designed to improve aerodynamics, this carbon fiber rear diffuser reduces drag and enhances stability at high speeds. Its precise contours optimize airflow under the car, promoting better handling and a smoother driving experience.

Installation is simple and hassle-free. The carbon fiber rear diffuser comes with all necessary hardware and is designed for seamless integration with your factory bumper for a professional, custom look.

Elevate your Audi S4 / A4 S Line with this premium carbon fiber rear diffuser from Ausen Performance—where style, performance, and craftsmanship meet.

Product Details:

  • Custom-made to order: Production 1-3 weeks, Delivery 1-2 weeks

  • Fitment: 2020–2021 Audi S4 / A4 S Line Sedan

  • Note: Custom-made products cannot be exchanged or returned

Recently Viewed

Eric N

Eric N

Skid plate has already saved me twice from having to spend $3k+ on a new cooling system, best preventative mod I've done

Aidan L

Aidan L

Got the M-Performance Wing and CF Hood vents, mounting points line up cleanly. Clear coat is smooth...

Sebastian C.

Sebastian C.

My front lip came in under a week, so happy with the results. Can't wait to do fenders next

Branson S.

Branson S.

Absolutely love how my diffuser looks, feels premium compared to other carbon I've had in the past.

Malcom M.

Malcom M.

Great fitment, good communication. Thank you Ausen