Genuine BMW M Performance Limited Slip Differential (LSD) 3 Series/4 Series F30 F31 F32 F33 F36 Manual RWD 335i 340i 435i 440i OEM Rear Diff Upgrade Part 33108659988

BMW OE M Performance Rear Axle Differential - F3x Manual RWD 335i 340i 435i 440i - Part 33108659988

Unlock real traction and confidence with the BMW factory performance rear final drive. This genuine OE unit replaces the standard open differential on manual rear wheel drive F30 F31 F32 F33 F36 models and transforms how your car puts power down. Expect stronger drive off the apex, calmer rear axle behaviour and repeatable grip in the dry and wet. If you want a factory-engineered solution that fits, works and lasts, this is the one to choose.

What you will feel

• Clean power delivery out of slower bends with reduced inside wheel spin
• More composed rear end on throttle lift and during braking into a corner
• Extra bite on wet roads and in variable UK weather
• Smoother, faster exits without fighting the stability systems
• Track day friendly behaviour with predictable lock-up, ideal for fast road and circuit use

Why choose the BMW OE unit

• Built by BMW to OEM standards for durability, noise control and long-term reliability
• Mechanical limited slip design that sends torque to the tyre with available grip
• Bolt-in replacement for eligible F3x manual rear wheel drive cars
• Reversible upgrade, keep your original diff for future refit if desired
• Genuine part number confirmation for peace of mind - PN 33108659988

How it works

The clutch-pack limited slip mechanism intelligently balances drive between both rear wheels. When one tyre starts to unload, the unit biases torque across the axle so you can get back on throttle earlier and with more control. Lock characteristics under acceleration and deceleration are tuned by BMW for a stable, confidence-inspiring feel on UK roads and at the circuit.

Vehicle compatibility

• 3 Series F30 F31 - 335i and 340i, manual transmission only, rear wheel drive only
• 4 Series F32 F33 F36 - 435i and 440i, manual transmission only, rear wheel drive only

Not suitable for xDrive. Not for automatic gearboxes.

Part number

33108659988

Specification notes

• Ratio I = 3.23, size 215W
• Genuine BMW Performance Part, engineered to OE NVH and durability standards

Fitment check before dispatch

We confirm compatibility prior to shipping. Add your UK registration or the last 7 digits of your VIN at checkout and our team will verify the correct unit for your car.

Installation

Professional fitting recommended. MJ Modifications offers supply and installation at our Warwickshire workshop. For a quotation, email info@mjmodifications.co.uk. We have installed this differential on customer cars and our own builds, and the improvement in traction, balance and throttle confidence is outstanding.

Fluids

Use the correct BMW lubricant specified for the M Performance limited slip unit. Top up only with the approved oil.

Customer feedback

Owners report faster corner exits, far less inside wheel spin and a more connected rear axle. For manual F3x N55 and B58 cars, this is one of the most rewarding drivetrain upgrades you can make without compromising day-to-day refinement.

Warranty

BMW manufacturer warranty applies on eligible vehicles when installed correctly and supplied against your VIN.

Common search terms

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