Catback Milltek Audi S4 B9, S5 F5 - ECE homologated - with primary muffler - Quad Jet-100 Carbon outlets - without sport diff.

Milltek Sport Exhaust System for Audi S4 B9 / S5 F5

Replacing the factory exhaust with a Milltek Sport system brings back the character that the engine of your Audi S4 B9 / S5 F5 is held back on in stock form: a rounder tone at idle that opens up clearly through the revs, with no artificial effects.

Technical specifications

• Milltek part number: SSXAU723
• Part type: Exhaust system
• Configuration: with valves
• Detail: ECE homologated, with primary muffler, quad Jet-100 Carbon outlets
• Tube diameter: 63.5 mm
• Outlets: 4 Jet outlets, 102 mm
• Tip finish: carbon
• Fitment information: Models without Sport Diff, with valves
• Material: aerospace-grade stainless steel
• Homologation: ECE / EC homologated
• Manufacturer: Milltek Sport (UK)

Compatible vehicles

• Audi S4 B9 3.0 Turbo V6 (without Sport Diff, Sedan, Avant, 2016-2018)
• Audi S5 F5 3.0 V6 T (without Sport Diff, Sportback, 2017-2018)

Not sure whether it fits your vehicle? Contact us with your chassis number (VIN) before ordering.

Our most frequently asked questions

• What about the neighbors in the morning? The valves are controlled as on the factory system: closed and discreet at startup or in comfort mode, fully open in sport mode.
• Homologation: this system is ECE / EC homologated, a real plus for driving with peace of mind and passing the contrôle technique.
• 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?

Milltek Sport designs and manufactures its exhaust systems in England, using mandrel-bent tubes to preserve the inner diameter and a fit developed on the vehicle. The result: a clean installation without modification, and a sound tuned to stay pleasant for everyday driving.

Further reading

• Exhaust systems with valves: how they work and should you keep them?
• Exhaust systems and the contrôle technique in France