BMW 1 Series M140i F20/F21 Axle-Back Exhaust Rear Box | Genuine BMW M Performance B58 Back Box / Rear Silencer Muffler (Tipless, Without Tips) for M140i & M140i xDrive | OEM Factory Upgrade Replacement Rear Section | Part No. 18302425908

BMW Factory Upgrade Rear Box for 1 Series M140i F20 F21 B58 | Genuine Part No. 18302425908

Elevate the soundtrack of your 1 Series while keeping everything OEM. This genuine BMW rear silencer assembly is the factory performance rear section for B58-powered M140i models, including all-wheel-drive variants. It is supplied without tailpipe finishers, making it ideal if you already have trims or want to choose carbon fibre or polished alternatives separately.

Why this genuine BMW rear section is the smart upgrade

• Authentic BMW component for perfect alignment and a hassle-free fit on F20 and F21 M140i, including xDrive
• Deeper, sportier tone outside with refined cabin comfort for everyday use
• OE-grade stainless construction for durability and corrosion resistance
• Direct replacement rear section that keeps the OEM look and quality
• Tipless design so you can retain your existing trims or add genuine BMW carbon fibre or chrome finishers

We have fitted this part to customer cars at MJ Modifications and feedback has been consistently excellent. Owners love the OEM-plus character, the factory-quality fit and the tasteful sound enhancement.

What you receive

Genuine BMW rear silencer assembly for the M140i, supplied without tailpipe finishers. Optional BMW carbon fibre or chrome tips are available separately.

Compatibility

• BMW 1 Series F20 M140i and M140i xDrive 5-door Hatchback, B58, from April 2016 to May 2018
• BMW 1 Series F21 M140i and M140i xDrive 3-door Hatchback, B58, from December 2016 to May 2018

Part number

18302425908

Fitting and installation

Professional installation recommended. For expert fitting, book with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Compatibility check before dispatch

To confirm this rear section suits your vehicle, provide your UK registration or the last 7 characters of your VIN at checkout and we will verify fitment.

Manufactured by

BMW Genuine M Performance Parts.

Warranty

Two years manufacturer warranty for UK customers and one year manufacturer warranty for international customers when a VIN is supplied on compatible vehicles.

Search-friendly terms

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