Wavetrac ATB LSD Built Differential for 215K 3.08 Final Drive Axle F20/F21 M135i, F20/F21 M140i, F22/F23 M235i, F22/F23 M240i, F34 340i

BMW F-series rear axle upgrade, built with a Wavetrac ATB centre for the 215K 3.08 final drive. Transform traction, corner exit speed and everyday drivability on your F20 F21 M135i, F20 F21 M140i, F22 F23 M235i, F22 F23 M240i and F34 340i with this complete uprated differential assembly. If you are chasing fast-road confidence, sharper launches and track day consistency, this helical gear limited slip delivers real-world grip where open diffs fall short.

Unlike conventional gear-driven diffs that stop transferring torque when a wheel goes light over kerbs or on slick surfaces, the Wavetrac’s patented internal wave device generates load inside the unit the moment an axle is unloaded. The result is uninterrupted drive to the tyre with traction, so you put power down cleanly through bumpy corners, wet roundabouts and uneven tarmac. More stability, more predictability and faster exits. Smooth is fast.

Why this built differential is the go-to BMW drivetrain upgrade

• Consistent power delivery when an inside wheel lifts or skims over kerbs, in rain or on low-grip roads
• Helical ATB design with a patented wave mechanism for continuous torque transfer at near zero load
• Carbon fibre bias plates maintain performance from new to high mileage for long-term consistency
• 9310 steel gears and robust billet or forged housings for strength you can rely on
• ARP fasteners throughout for durability under hard use
• Transparent behaviour with stability control during normal driving, with none of the push or understeer often felt with clutch plate diffs
• Gear-driven, so no clutch packs to wear and no chatter, ideal for daily use and spirited road driving

Proven on UK roads and track days
We have run this upgrade ourselves and supplied it to many customers who report noticeably better traction out of tight bends, reduced one-wheel peel and smoother throttle application in mixed weather. Whether you enjoy B-roads, circuit time or simply want a more planted rear end, this is a serious performance differential that enhances confidence and lap-to-lap consistency.

Vehicle compatibility

• BMW F20 F21 M135i
• BMW F20 F21 M140i
• BMW F22 F23 M235i
• BMW F22 F23 M240i
• BMW F34 340i

For 215K final drive with 3.08 ratio. Built differential assembly for direct fit to the specified rear axle type.

Ideal uses and benefits

• Fast road and daily driving in all weathers, wet and dry
• Track days, sprint, hillclimb, time attack and drag strip launches
• Tuned and standard power levels seeking better traction and control
• Improved corner exit speed, reduced inside wheel spin and enhanced stability

Fitting and support
Professional installation recommended. MJ Modifications offers supply and fit in Warwickshire with setup advice for road and track. For a fitting quote or to check axle details, email info@mjmodifications.co.uk.

Search-friendly terms to help you find this upgrade
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