Milltek Sport OPF/GPF Back Particulate Filter-Back Exhaust System with GT-115 Titanium Tips for BMW M135i xDrive (F40) 5 Door 2019+

Transform your BMW F40 M135i xDrive with a UK-crafted performance rear section featuring GT-115 titanium tailpipes. This Milltek setup sits after the factory petrol particulate filter, unlocking a richer soundtrack, crisper response and a premium motorsport look without unwanted cabin boom. Built for everyday drivability and weekend fun, it is the ideal sound and style upgrade for the 2019 onwards five door M135i AWD hot hatch.

Highlights

• Hand built in Britain from aerospace grade T304 non-magnetic stainless steel for strength and corrosion resistance
• Flow-optimised, full mandrel-bent tubing maintains smooth radii to help responsiveness versus stock
• Acoustically tuned for a deeper, sportier note with minimal drone inside the cabin
• GT-115 titanium tailpipe finishers deliver a heat resistant, lightweight and high-end motorsport aesthetic
• Post-filter layout retains the factory GPF/OPF while enhancing tone and rear-end presence
• Durable materials and precision fabrication for long-term reliability

Why this suits the F40 M135i xDrive

The M135i xDrive platform responds brilliantly to a quality rear section. Enlarged bore sizes versus the OE parts and smooth, constant-radius bends help the turbo breathe more freely, while Milltek’s development work ensures the soundtrack stays refined on the motorway. The titanium GT-115 outlets sharpen the stance of the all-wheel-drive hot hatch and look superb against any body colour.

Compatibility

BMW M135i xDrive F40, five door, 2019 onwards. Designed to work after the factory gasoline particulate filter, keeping the OE filter in place.

Real-world results

We have fitted this Milltek system to multiple customer cars and run it on our own builds. Feedback is consistently positive. Owners praise the quality of the welds and materials, the tasteful volume increase, the lack of intrusive resonance and the standout titanium tips. It is a confidence-inspiring, daily-friendly performance upgrade.

Technical focus

• T304 stainless throughout silencers and pipework for longevity in UK conditions
• Carefully balanced internal design for a clean, sporty tone under load and a calmer note on cruise
• Precision-made GT-115 titanium outlets for a premium finish and reduced tail-end weight

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Professional fitting

Want it installed perfectly the first time. Book professional fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk. Our team has hands-on experience with this exact F40 M135i setup and will ensure a clean, precise fit.

Upgrade the soundtrack and finish of your M135i today with this Milltek rear section and GT-115 titanium outlets. Premium materials, engineered tone and head-turning style for the BMW F40 platform.