Milltek Sport OPF/GPF-Back Axle-Back Performance Exhaust, Quad 100mm Polished GT100 Tips for BMW 3 Series G20 M340i xDrive Saloon/Sedan 2019–2021 (B58) T304 Stainless Backbox/Rear Silencer Upgrade – SSXBM1158

Milltek rear section sports system with quad 100 mm polished GT100 tailpipes for BMW 3 Series G20 M340i xDrive Saloon 2019 to 2021 - SSXBM1158

Give your B58-powered M340i the soundtrack and presence it deserves with this UK-made rear exhaust section from Milltek. Part number SSXBM1158. Designed to fit after the petrol particulate filter, it retains the factory OPF/GPF while transforming tone and appearance with stunning quad 100 mm polished finishers.

Handcrafted from premium T304 stainless steel and precision mandrel bent, this performance rear system releases a deeper, cleaner note with crisp upshifts and zero unwanted drone. The result is an OEM-plus enhancement that looks as good as it sounds, delivering a purposeful motorsport character without compromising day-to-day comfort.

Why enthusiasts choose it

• Specific to BMW 3 Series G20 M340i xDrive Saloon 2019, 2020, 2021 with petrol particulate filter retained
• Milltek reference: SSXBM1158
• Quad 100 mm polished GT100 tailpipes for an aggressive factory-plus rear end
• T304 stainless construction for long-term durability and corrosion resistance
• Mandrel-formed pipework for smooth gas flow and a refined, sporty soundtrack
• Engineered for minimal cabin resonance with a rich tone outside
• Requires cutting of the original system for installation

Real-world results

We have fitted and driven this system on customer cars and our own demonstrators. Feedback is consistently positive: tighter, more characterful sound on throttle, a premium visual upgrade thanks to the mirror-polished quad outlets, and the build quality you expect from a leading UK manufacturer.

Compatibility

• Vehicle: BMW G20 M340i xDrive Saloon with B58 3.0 turbo petrol
• Years: 2019 to 2021 pre-LCI models with OPF/GPF
• Configuration: rear section that fits after the particulate filter
• Tailpipes: GT100 polished, 100 mm, quad exit

Fitting and support

Professional installation recommended. The original exhaust requires a cut to fit this rear section. Book expert fitting with MJ Modifications in Warwickshire. Request a quote: info@mjmodifications.co.uk.

Part number

SSXBM1158

Search terms our customers use

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