Milltek Valve Sonic Cat-Back Exhaust Audi S4 B8.5, S5 8T - Valve Sonic Version - Resonated + Rear Muffler - Polished Quad GT100

Milltek Sport Exhaust System for Audi S4 B8.5 / S5 8T

On the Audi S4 B8.5 / S5 8T, the original exhaust is designed for quietness and regulations. This Milltek Sport stainless steel exhaust system brings back the engine's voice with a refined, full and deep sound, the one that built the reputation of the British brand.

Technical specifications

• Milltek part number: SSXAU407
• Part type: Exhaust system
• Configuration: resonated (with intermediate muffler), with valves
• Detail: Valve Sonic version - With intermediate muffler + valved rear muffler - Quad GT100 polished stainless steel
• Tube diameter: 60.3 mm
• Outlets: 4 GT100 outlets of 100 mm
• Tip finish: polished stainless steel
• Fitting information: ValveSonic Electronic Valved System
• Material: aerospace-grade stainless steel
• Manufacturer: Milltek Sport (UK)

Fits the following vehicles

• Audi S4 B8.5 3.0 TFSi 333 hp (2012-2015)
• Audi S5 8T 3.0 TFSI B8.5 (Coupe - Cabriolet, 2011-2016)
• Audi S5 8T 3.0 TFSI B8.5 (Sportback, 2012-2016)

Not sure about fitment for your vehicle? Contact us with your VIN before ordering.

Most frequently asked questions

• Highway drone? It is the number one concern on forums. This version keeps an intermediate (resonated) muffler: the sound stays full under acceleration, but the system stays calm at steady speed, ideal for everyday driving.
• What about the neighbors in the morning? The valves are controlled as on the original: system closed and discreet on cold start or in comfort mode, fully open in sport mode.
• Fitting: the system uses the original mounting points. A repair shop with the right equipment typically fits it in one to two hours.

Why choose Milltek Sport?

Feedback from owners most often highlights the fit quality and a deep sound that is present but never harsh. This is the hallmark of Milltek Sport, a British manufacturer specializing in stainless steel exhausts.

Going further

• Cat-back exhaust, resonated or non-resonated: which one is right for your car?
• Valved exhaust system: how does it work and should you keep the valves?