BMW G20 3 Series M340

BMW G20 M340i B58D Rear Box Upgrade - Factory Axle-Back Silencer

Give your 3 Series the soundtrack it deserves with the official BMW rear section for the G20 M340i and M340i xDrive. This factory-built back box delivers a richer, sportier tone from the B58D turbo six while keeping refinement intact for daily use. Crafted from high grade stainless steel and engineered to BMW standards with computer aided development and structural analysis, it fits like original equipment and looks the part.

Expect a deeper note under load, a crisp bark on upshifts, and relaxed cruising with no unwanted drone. Gas flow is improved thanks to a reduced restriction design, supporting the engine’s performance potential without compromising reliability or comfort. This is the premium rear silencer choice for owners who want an authentic enhancement with perfect fit and finish.

Key benefits

• Original BMW rear section for G20 M340i and M340i xDrive with the B58D engine
• Fuller, more characterful soundtrack with everyday refinement
• Lower exhaust resistance for more efficient flow
• Stainless construction for durability and corrosion resistance
• Direct replacement using factory mounting points and hangers
• Precision developed for OEM alignment and appearance

Vehicle compatibility

• BMW 3 Series G20 Saloon M340i and M340i xDrive, B58D, 2019 to present

Part number

18302464492

What our customers say

We have installed this rear silencer for G20 M340i owners and the feedback has been excellent. Clients consistently praise the deeper tone, OEM fit and the way it elevates the driving experience without sacrificing comfort.

Installation

Professional fitting recommended. MJ Modifications offers expert installation in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Compatibility check

We will confirm suitability before dispatch. Please provide your UK registration number or the last 7 digits of your VIN at checkout.

Warranty

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

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