MMR Performance Billet Oil Filler/Engine Oil Cap - Black Anodised CNC Machined 6061-T6 Aluminium, Locking | BMW 1 Series F40 & 2 Series Gran Coupe F44 | Fits B38 B48 B37 B47 Petrol/Diesel | Valve/Rocker Cover Cap Upgrade Replacement OE 11128655331

Billet Alloy Engine Oil Cap Upgrade for BMW F40 and F44

Lift your bonnet to something special. This MMR Performance machined alloy oil cap delivers a premium black anodised finish, a precise spring-loaded lock and a satisfying, positive click every time you top up. Crafted from solid 6061 aluminium for strength and longevity, it replaces the tired plastic cam cover cap and gives your engine bay a clean, purposeful look while helping minimise the light misting that older OE caps can allow.

Engineered for everyday usability as well as style, the cap features a grippy profile for easy removal when hot, plus an updated insert that lets you align the logo at either 0 or 90 degrees for a neat, factory-plus presentation on both longitudinal and transverse layouts. It is the small detail that transforms the whole bay.

Key reasons enthusiasts choose this cap

• Beautiful black anodised finish for a stealth, OEM-plus appearance
• CNC machined from 6061 billet aluminium for durability and precision
• Spring-actuated locking mechanism that engages securely every time
• Selectable logo orientation at 0 or 90 degrees for perfect alignment
• Knurled and contoured edges for confident grip even in a hot bay
• Helps reduce weeping compared with ageing plastic valve cover caps
• Complements other under-bonnet dress-up components for a cohesive build

Compatibility and OE cross-reference

Designed for BMW 1 Series F40 and 2 Series Gran Coupé F44 models running the rounded factory oil filler design on B38, B48, B37 and B47 engines, petrol and diesel. Please compare the underside of your existing cap with our images to confirm fitment.

Direct replacement for the OE cap reference: 11128655331 also written as 11 12 8 655 331.

Installation guidance

• Re-use your original seal from the factory cap to ensure correct seating.
• Extended exposure to high heat may gradually affect the appearance of anodised finishes.

Professional fitting

Want it installed by experts. Book with MJ Modifications in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Proven on our own cars

We run this MMR cap on our builds and customer vehicles. Feedback is consistently positive on the top-tier finish, the solid feel and the confidence-inspiring lock. It is a subtle touch that makes your BMW engine bay look and feel premium every time you open the bonnet.

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