Genuine BMW M Performance B47 Diesel Active Sound Sport Exhaust Back Box/Muffler Rear Silencer (Axle-Back) F30 F31 F32 F33 F36 3 & 4 Series 318d 320d 418d 420d xDrive | OEM Rear Section No Tips | PN 18302407193

BMW B47 F3x Active Sound Backbox - Genuine M Performance Rear Section without Tail Trims - Part No. 18302407193

Give your 3 Series or 4 Series diesel the soundtrack it deserves with BMW’s factory-developed Active Sound rear section for B47 engines. This genuine M Performance backbox delivers a deeper, more purposeful tone while keeping long‑journey refinement. In ECO PRO it stays calm, in Comfort it adds a tasteful growl, and in Sport it brings a richer, more engaging note for those weekend blasts.

We have installed and run this system ourselves at MJ Modifications, and customer feedback has been consistently excellent. Expect a premium OEM+ feel, perfect fitment and a quality sound character that complements daily driving and spirited use alike.

Why this factory sport backbox stands out

• Authentic BMW M Performance rear section for precise fit and finish
• Drive mode linked sound character - quiet when you want it, assertive when you do
• Engineered specifically for B47 four-cylinder diesel applications on the F3x platform
• OEM reliability and integration - the right choice for an upgrade that feels factory
• Axle-back design enhances tone without compromising day-to-day usability

Included: Active Sound rear box assembly only. Tailpipe trims are not included and are available separately.

Compatibility - diesel models only

• BMW 3 Series F30 LCI Saloon 2014-2018
  • 318d, 318dx, 320d, 320d ed, 320dx
• BMW 3 Series F31 LCI Touring 2014-2019
  • 318d, 318dx, 320d, 320d ed, 320dx
• BMW 4 Series F32 Coupe 2014-2017 and F32 LCI 2016-2019
  • 418d, 420d, 420dx
• BMW 4 Series F33 Convertible 2014-2017 and F33 LCI 2016-2019
  • 420d
• BMW 4 Series F36 Gran Coupe 2014-2017 and F36 LCI 2016-2019
  • 418d, 420d, 420dx

Not for petrol models.

Fitting and support

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

Compatibility check before dispatch

We will verify fitment before shipping. Please provide your UK registration or the last 7 of your VIN at checkout to ensure you receive the correct part.

Part number

18302407193

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 valid VIN is supplied at checkout on compatible vehicles.

Important notes

• This listing is for the Active Sound backbox only. Tailpipe tips are sold separately.
• Designed for diesel vehicles listed above.

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