
Cat-Back Exhaust
Milltek Resonated Cat-Back Exhaust | Lexus GX 550 3.4 Turbo V6 - Burnt Titanium TipsMilltek

Cat-Back Exhaust
Brand: Milltek
Part #: SSXAU644
SKU: MK-SSXAU644
Milltek Resonated Cat-Back Exhaust System for Audi B9 S4 and S5 (non-sport differential models). Direct factory fitment replacement using OEM hangers, no modification required. 2.50" (63.5mm) mandrel-bent T304L stainless steel construction with quad GT-90 polished tips. Engineered tone character balances sportier note with refinement-resonated design targets OE resonance points for OE+ sound profile without excessive drone. T304Lstainless steel resists corrosion and thermal stress. CNC-formed joints and hand-finished construction. Dyno-proven improved exhaust flow supports modest performance gains across the power band. Fitment • Audi S4 B9 3.0L Turbo V6 Saloon/Sedan & Avant (non-sport differential) 2016+ • Audi S5 B9 3.0L Turbo V6 Sportback (non-sport differential) 2017+ Cat-back design: replaces factory exhaust from rear of secondary catalytic converter rearward. OEM valves and electronic controls remain unaffected. Fits stock suspension and body. Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.

Cat-Back Exhaust
Milltek Resonated Cat-Back Exhaust | Lexus GX 550 3.4 Turbo V6 - Burnt Titanium TipsMilltek

Cat-Back Exhaust
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Cat-Back Exhaust
Milltek Resonated Cat-Back Exhaust | Lexus GX 550 3.4 Turbo V6 - Cerakote Black TipsMilltek

Cat-Back Exhaust
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