Audi A4 B8 Base Sedan Carbon Fiber Rear Diffuser, 2008–2011 Pre-Facelift

Carbon Fiber Rear Bumper Diffuser for Audi A4 B8 Base Sedan

Add a gloss carbon-fiber accent to the lower rear bumper of your pre-facelift A4. The source describes a replacement for the factory plastic diffuser, not a complete rear bumper or exhaust assembly.

Vehicle fitment

• Audi A4 B8 Base Sedan, 4-door.
• Listed model years: 2008–2011, pre-facelift.
• Not for A4 S line or S4 models.

Confirm your exact model year, Base rear bumper, original diffuser, exhaust outlet layout and mounting points before ordering. The hidden fitment tags include A4 Quattro entries and extend to 2012, but the public specification does not separately confirm drivetrain-specific applications or 2012 fitment. Verify these rather than treating the tags as additional confirmed compatibility. Avant, other chassis, facelift bumpers and modified bumpers are not established applications.

Material and finish

• 3×3 weave carbon fiber, according to the original specification.
• High-gloss finish with a UV-resistant coating.
• Dry-carbon construction and a specific curing process are not documented.

Installation

Self-tapping screws are listed as included, and professional installation is recommended. The source describes removing the factory diffuser and fitting this replacement.

Although the original instructions state that no cutting or modification is required, the listed self-tapping screws do not establish that every installation can use existing holes. Confirm the fastening arrangement and whether drilling is necessary before making permanent changes.

Test-fit and check alignment, mounting points, exhaust clearance and access around adjacent rear equipment before final fastening. Do not force installation if the bumper or mounting profile does not match.

Package details

The source lists a replacement diffuser and self-tapping screws. Exact piece count, dimensions, exhaust-opening measurements and screw quantities are not specified; confirm package contents before installation. Exhaust components are not listed as included.

Frequently asked questions

Does it fit an A4 S line or S4?
No. Both are explicitly excluded by the source.

Does it fit a 2012 A4?
The public specification lists 2008–2011. Hidden tags include 2012, so that application requires separate confirmation.

Does it replace the original diffuser?
Yes. The source identifies a replacement-style part rather than an overlay.

Will it fit every exhaust arrangement?
Universal exhaust compatibility is not established. Compare the openings and your exact exhaust layout before ordering.

Does it improve aerodynamic performance?
No measured aerodynamic, handling or fuel-economy results are supplied, so those effects are not promised.