Genuine BMW M Performance Limited Slip Differential (LSD) F20 F21 F22 F23 1 Series/2 Series M135i M140i M235i M240i OEM Rear Differential Upgrade Part No. 33108659987

BMW F20 F21 F22 F23 rear diff upgrade for M135i, M140i, M235i, M240i

Give your rear-wheel-drive BMW the traction it deserves. This genuine BMW performance final drive transforms how your 1 Series and 2 Series puts power down, tightening up corner exits, reducing inside-wheel spin and delivering confident acceleration in all weathers. It is a factory-engineered, bolt-in rear axle upgrade that brings road, fast-road and track-day control to the F2x platform without compromising everyday refinement.

As a BMW catalogue part, build quality, durability and integration are exactly as you would expect from the manufacturer. It is an OEM-plus driveline enhancement that keeps your car authentic and reversible. Part number: 33108659987.

What you will feel

• Stronger drive out of bends with both rear tyres doing work instead of one wheel spinning away energy.
• Cleaner throttle application in the wet, improved stability on uneven surfaces and far more predictable balance at the limit.
• Smoother, faster corner exits and less intervention from the brakes for a more natural, mechanical grip feel.
• Confidence-inspiring behaviour on B-roads and a measurable benefit for track days and sprints.

Why we rate it

We run this unit on our own cars and have installed it for many F2x owners. Feedback is consistently positive: better traction, more precise handling and happier drivers. It is one of the most rewarding driveline mods you can make to these models.

Fitment guide

N55 models

• F20 F21 1 Series M135i manual and automatic
• F22 F23 2 Series M235i manual and automatic

B58 models

• F20 F21 1 Series M140i manual only
• F22 F23 2 Series M240i manual only

If you have an M140i or M240i with the B58 and automatic transmission, please see our other listing for the correct unit.

Key advantages

• Mechanical slip-limiting action balances torque across the rear axle for real grip you can feel.
• Locking characteristics suited to fast road and circuit driving for a stable, predictable rear end.
• Factory component with proper testing and longevity, designed to integrate with standard electronics.
• Direct replacement assembly that can be removed later if you wish to return to stock.

Recommended oils

• Genuine BMW M Performance LSD Oil 1 Litre
• Liqui Moly Fully Synthetic Hypoid Gear Oil GL5 LS SAE 75W-140 1 L

Suitable for service intervals and top-ups as required.

Fitting and support

Professional installation recommended. We can supply and fit at MJ Modifications in Warwickshire. Request a fitting quote: info@mjmodifications.co.uk.

Compatibility check before dispatch

To confirm the correct assembly for your vehicle, we run a compatibility check before shipping. Please provide your UK registration number or the last 7 of your VIN at checkout.

Warranty

Two years manufacturer warranty for UK customers and one year manufacturer warranty for international customers when a VIN is provided at checkout on compatible vehicles.

Manufactured by

BMW. Genuine BMW performance driveline component.

Search terms customers use

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