BMW 1 Series M140i M Performance Sports Exhaust – Rear Silencer / Back Box / Muffler (Axle Back Rear Section) | F20 F21 LCI B58 | Genuine OEM for M140i & M140i xDrive

BMW 1 Series M140i Sports Rear Silencer by M Performance, F20 F21 LCI, B58

Give your B58 straight six the voice it deserves with the official BMW M Performance sports rear silencer for the M140i and M140i xDrive. This factory upgrade replaces the standard rear box with a higher flow, acoustically tuned unit that delivers a deeper, richer note and a more purposeful character while keeping full OEM quality, perfect fitment and everyday refinement.

Built by BMW for the facelift F20 and F21 1 Series, this axle back solution keeps the car authentically BMW and integrates seamlessly with the original mounting points. No fuss, no compromise, just a premium sound upgrade backed by BMW engineering.

Why enthusiasts choose this upgrade

• Official BMW M Performance rear section for the M140i and M140i xDrive
• Designed for the B58 powered F20 LCI and F21 LCI platforms
• Deeper tone with increased presence compared to the stock rear silencer
• Improved flow characteristics for better breathing
• Factory-grade materials, finish and durability
• Direct bolt-on to OEM hangers and connections
• Keeps your 1 Series upgrade fully BMW approved and insurance friendly

Fitment

Compatible with BMW 1 Series M140i and M140i xDrive, F20 LCI and F21 LCI, B58 engine. If you are unsure on compatibility, contact us and we will be happy to help before you order.

Tailpipe trims

Tailpipe finishers are not included. You can reuse your existing tips or purchase BMW M Performance tips separately if you want a different look.

Tried and loved by our customers

We have installed this sports rear box on our own builds and many customer M140i cars. Feedback is consistently positive, highlighting the more engaging soundtrack, subtle cabin refinement and the reassurance of a genuine BMW upgrade.

Professional installation

We recommend professional fitting. MJ Modifications offers expert installation at our workshop in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Delivery and lead time

Supplied directly from BMW. Typical lead time is around 7 working days, subject to BMW availability and logistics. If you need an accurate ETA, please email us before ordering.

Search terms buyers use

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Order today to elevate the character of your M140i with a factory-engineered soundtrack and flawless OEM fitment.