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Exhaust› Exhaust Pipes, Systems and Components

Milltek

Non-Resonated Cat-Back Exhaust System

Name: Non-Resonated Cat-Back Exhaust System
Brand: Milltek
SKU: SSXAU337

$1,867.33

SKU: SSXAU337

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Non-Returnable Item

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Moderate — 2–4 hours

Overview

The Milltek SSXAU337 is a non-resonated cat-back exhaust system designed as a direct replacement for the original system. It is constructed from aerospace-grade type 304, non-magnetic stainless steel for durability. This system allows the owner to choose an increase in exhaust volume and a more aggressive tone.

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The Milltek SSXAU337 is a non-resonated cat-back exhaust system engineered as a direct replacement for the original exhaust on the Audi RS4 B8 Avant. The 70mm (2.76-inch) diameter pipework is mandrel-bent to ensure consistent radius bends and optimized gas flow. Bore diameters are carefully enlarged over stock to enhance performance without sacrificing mid-range torque. The installation is estimated to take between 2 to 2.5 hours. It is important to note that this system is not EC-approved and is not a race system.

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	Milltek
Part Number	SSXAU337
Category	Exhaust

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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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