MMR Performance N55 3.0 Turbo Oil Catch Can / Air Oil Separator AOS Kit - BMW F2x F3x F20 F21 F22 F23 F30 F31 F32 F33 M135i M235i 335i 435i - Baffled PCV Crankcase Breather Catch Tank, Direct-Fit - MMR17-0501FK (2015-2019)

Air Oil Separator Upgrade for BMW F-Series N55 3.0 Turbo Six

Stop oily blow-by before it reaches your intake system and keep your N55 running crisp and consistent. This MMR Performance air oil separator is a direct bolt-on crankcase breather upgrade for BMW F-series models, engineered to strip oil mist and moisture from the PCV stream so it never coats your intercooler, charge pipes or inlet valves. Expect a cleaner intake path, reduced valve deposits and reliable, repeatable performance on the road and track.

Part number: MMR17-0501FK

Why this breather system belongs on your N55

• Mitigates intake valve coking common on direct injection engines
• Keeps intercooler and boost pipework cleaner for longer
• Helps maintain consistent power delivery and throttle response
• Promotes cleaner combustion by reducing oil contamination in the charge air

Premium construction and OE-style fit

• Beautifully machined T-6061 aluminium canister, anodised in high-gloss black
• Internal baffling and separation for efficient oil and vapour control
• Integral dipstick for quick level checks and hassle-free draining
• PTFE-lined hoses with crimped motorsport-grade fittings for a leak-free install
• CNC billet mounting bracket for a tidy, OEM-plus placement on the inner wing
• Billet cam cover connector replicates the factory interface for perfect alignment
• All fixings supplied for a straightforward, plug-and-play installation

We run this exact setup on our own N55 builds and it has been superb. Customers consistently report cleaner intake tracts, less oil residue in the boost system and a noticeable improvement in long-term consistency.

Vehicle compatibility

This MMR crankcase ventilation upgrade fits BMW F-series N55 turbo petrol models:

• 1 Series F20 F21 M135i and M135i xDrive 2015 to 2019
• 2 Series F22 F23 M235i and M235i xDrive 2015 to 2019
• 3 Series F30 F31 335i and 335i xDrive 2015 to 2019
• 4 Series F32 F33 435i and 435i xDrive 2015 to 2019

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Fitting and support

Designed for a clean, bolt-on install using the included hardware and bracketry. Prefer professional installation and a seamless finish? Book fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Choose the MMR Performance air oil separator if you want an OEM-quality solution that keeps your N55 breathing clean, protects against valve deposits and looks as good as it performs. Part number MMR17-0501FK.