BMW 340i/340ix 440i/440ix M Performance Exhaust - Genuine OEM Rear Silencer Muffler Backbox, B58 F30 F31 F32 F33 F36, Twin Tailpipes (Chrome/Carbon), PN 18302406953

Original BMW M Performance Rear Section for B58 F3x 3 Series and 4 Series

Give your B58 straight six the voice it deserves with the factory performance rear box from BMW. This genuine axle-back assembly replaces the standard rear silencer on F30 F31 F32 F33 F36 models fitted with the B58 engine, delivering a deeper, richer note and a premium twin outlet finish. It is the authentic OE upgrade for drivers who want a sharper soundtrack, refined cabin manners and perfect fitment.

Part number: 18302406953

Why enthusiasts choose this OE performance rear box

• Sportier tone with a smooth, straight six character and minimal cabin resonance
• Improved flow characteristics for the rear section to complement further tuning
• High grade stainless steel construction for long term corrosion resistance
• Twin round outlets with M logo finishers, available in chrome or carbon fibre
• Direct replacement using factory hangers and original mounting points
• Designed and validated by BMW for the B58 platform for consistent quality

We have installed this system on customer cars and on our own builds. Owners consistently report a noticeable step up in character without unwanted drone, excellent fit and finish and the reassurance that comes with an original BMW M Performance part.

Compatible vehicles

• 3 Series F30 Saloon and F31 Touring 340i and 340i xDrive
• 4 Series F32 Coupe, F33 Convertible and F36 Gran Coupe 440i and 440i xDrive

Applies to B58-equipped models. To retain BMW warranty cover, installation is for automatic transmission vehicles only.

Tailpipe finishers

• Chrome tips with M logo, PN 18302354364
• Carbon tips with M logo, PN 18302355889

Fitment verification before dispatch

We check compatibility prior to shipping. Add your UK registration or the last 7 digits of your VIN at checkout and we will confirm suitability for your specific F3x B58 chassis.

Professional installation

Fitting available at MJ Modifications in Warwickshire. For a quote, email info@mjmodifications.co.uk. We provide OEM-quality installation and advice for your B58 performance upgrade.

Manufactured by

BMW M Performance Parts. Genuine original equipment.

Warranty

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

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