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Sale

ECS Tuning

Forged Carbon Fiber Rear Diffuser

Name: Forged Carbon Fiber Rear Diffuser
Brand: ECS Tuning
SKU: ES4490851
Price: 578.19 USD
Availability: InStock

$998.99 $578.19 Save $420.80

SKU: ES4490851

In Stock

Ships by Aug 29

Free Shipping over $200

$100 Minimum Order

30 Days Return

Description

The ECS Tuning Forged Carbon Fiber Rear Diffuser is engineered to provide an aggressive and sporty aesthetic upgrade for the rear of your B8.5 Audi S4 or A4 S-Line. It perfectly complements the factory appeal of the facelifted B8 models, setting your vehicle apart. Installation is straightforward and requires no drilling, cutting, or modifications. For a cohesive exterior transformation, ECS Tuning recommends pairing this rear diffuser with their Carbon Fiber Trunk Spoiler and Side Blades.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

Brand	ECS Tuning
Part Number	ES4490851
Category	Exterior Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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