MMX Billet Differential Insert Set for Fxx BMW 1 Series, 2 Series, 3 Series, and 4 Series
MMX Performance’s Billet Differential Insert Set is engineered in the UK to dramatically improve rear-end stability and driving precision on BMW F2x and F3x chassis vehicles. Designed to eliminate unwanted movement in the factory rubber differential mounts, these precision-machined billet aluminum inserts fill the factory voids and limit vertical deflection under load. The result is sharper suspension response, improved geometry under cornering, and enhanced traction—especially when driving at the limit. Installation is straightforward, reversible, and takes under an hour. Unlike rubber-based alternatives, these aluminum components will not degrade over time, offering a permanent upgrade in drivability and rear-end composure. Despite their performance benefits, customer feedback consistently reports little to no increase in NVH (noise, vibration, and harshness), making this an ideal solution for both daily-driven and performance-oriented applications. Compatible with petrol, diesel, manual, and automatic F20, F21, F22, F23, F30, F31, F32, F33, and F36 models, the MMX insert kit also enhances the performance of aftermarket sway bars and suspension systems.
Features
- Black Anodized 6061-T6 Billet Aluminum with stainless setter retaining
- Designed to reduce differential movement while keeping NVH to a minimum
- Reduces differential movement under acceleration, gear shift and deceleration
- Fills OE bushing voids
- Helps maintain correct suspension geometry
- Simple installation
Applications
- BMW 1 Series: F20 (2012-2019)
- BMW 2 Series: F22, F23 (2014-2021)
- BMW 3 Series: F30, F31 (2012-2019)
- BMW 4 Series: F32, F33, F36 (2013-2020)
About MMX Performance
MMX Performance is a UK‑based specialist in performance parts for BMW and MINI vehicles, crafting high‑quality upgrades that blend precision engineering, rigorous testing, and motorsport heritage. Driven by enthusiast culture, MMX designs its products in the UK — often putting them through track validation — to ensure durability, fitment accuracy, and on-road performance. Their catalog spans drivetrain components, spacers, hardware, and chassis enhancements, all tailored to elevate both the driving experience and visual appeal of BMW and MINI models.
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