Transform the rear of your BMW 3 Series G20 Saloon or G21 Touring with the Genuine BMW M340i M Performance Rear Diffuser in OEM Gloss Black PUR or Real Carbon Fibre. This factory BMW M Performance rear valance is the go-to upgrade for drivers who want an aggressive, premium, OEM-plus finish with perfect fitment and integration. If you are searching for BMW G20 rear diffuser, BMW G21 rear diffuser, M340i diffuser, M Performance rear diffuser, genuine BMW diffuser or OEM BMW rear valance, this is the exact part you want.
Built by BMW for BMW, this M Performance diffuser delivers the unmistakable motorsport-inspired look with a flawless fit, sharp lines and a high quality surface finish that complements the 3 Series design. Choose High Gloss Black PUR for a deep, mirror-like shine that ties in with shadowline trims, or upgrade to hand-made Carbon Fibre for a true performance appearance with visible weave.
Key reasons to choose the Genuine BMW M Performance diffuser
- Genuine BMW M Performance part for perfect OE fitment and finish
- Sporty, aggressive rear-end styling that looks factory and premium
- Precisely matched to BMW 3 Series G20 Saloon and G21 Touring geometry
- Two finishes - High Gloss Black PUR or Real Carbon Fibre
- Gloss Black PUR is UV, temperature and water resistant for long-lasting shine
- Carbon Fibre option is hand-made for an authentic M Performance look
- Ideal for M340i and compatible G20 and G21 models as listed below
Finish options
- High Gloss Black PUR - deep gloss finish that complements shadowline and high gloss trims
- Carbon Fibre - real carbon weave for a premium M Performance appearance
Compatibility
High Gloss Black Diffuser
- BMW 3 Series G20 Saloon (2017 - 2021)
- 318d, 320d, 320dx, 320i, 320ix, 330d, 330dx, 330e, 330i, 330ix, M340i, M340ix
- BMW 3 Series G21 Touring (2018 - 2021)
- 318d, 320d, 320dx, 320i, 330d, 330dx, 330i, M340ix
Please note: The High Gloss Black Diffuser requires the Genuine BMW 3 Series G20 G21 M Performance High Gloss Black Rear Bumper Trim. There are two trims depending on model - one for 320d, 320i, 330d and 330i, and one for M340i and M340ix.
Carbon Fibre Diffuser
- BMW 3 Series G20 Saloon (2017 - 2021)
- M340i, M340ix
- BMW 3 Series G21 Touring (2018 - 2021)
- M340ix
Please note: The Carbon Fibre Diffuser requires the Genuine BMW 3 Series G20 G21 M Performance High Gloss Black Rear Bumper Trim for M340i and M340ix.
Part numbers
- 51192455821 - High Gloss Black
- 51192459740 - Carbon Fibre
Genuine BMW quality and warranty
Manufactured by BMW M Performance Parts. Two years manufacturer warranty when the VIN is provided during checkout.
Compatibility check
We verify fitment before dispatch. Provide your UK registration number or the last 7 of your VIN at checkout to ensure the part suits your vehicle.
Professional fitting
For installation, we recommend booking with Nforcd in Warwickshire. Request a fitting quote at Sales@nforcd.com.
Tried, fitted and loved by our customers
We have used and fitted these genuine BMW M Performance rear diffusers on G20 Saloon and G21 Touring models, and our customers consistently praise the fit, finish and the way it transforms the rear end. If you want the best OEM look for your BMW 3 Series, this is the diffuser to choose.
Common search terms
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