E90 E92 E93 M3 Diff Fluid

Introduction:
The BMW E90 E92 E93 M3 uses a Limited Slip Diff known as a Large Case 'type 215'.
This means it has a crown wheel diameter of 215mm and even though it's known as a Large Case, it's internal (Crown Wheel) setup is unique when compared with the older style E36/E46 M3 (which used a 'type 210' Large Case).

Original LSD Fluid change (option 1): £89.
A BMW TIS document online shows the fluid which BMW call 'SAF-XJ' is just an old trade name for the currently available Castrol Syntrax 75w140:
https://www.newtis.info/tisv2/a/en/e92-m3-cou/repair-manuals/33-rear-axle-rear-wheel-drive-guide/33-10-rear-axle-final-drive/1GdD0La
We keep approx 40 Litres of Castrol Syntrax 75w140 in stock at anyone time.

Updated LSD Fluid change (option 2): £179.
Regardless of it's newer and slightly larger design, the E90 E92 E93 M3 LSD is still susceptible to the traditional BMW M3 'Diff Grinding' noises on tight cornering and slow speed manoeuvring.

This M3 Diff Grinding/Skipping noise has been long associated with the E46 M3, but as the E90 E92 E93 M3 models get older and experiences more miles and therefore wear, we're starting to see more complaints of Diff Noises in the E9x M3 platform as well.

Here's a link to an already-leaked BMW Technical Document that can easily be found on the internet which shows this known problem and recommends a specially Modified Diff Fluid which has an accurate factory-premixed additive called FM Booster:

and here:
https://www.newtis.info/tisv2/a/en/e92-m3-cou/repair-manuals/33-rear-axle-rear-wheel-drive-guide/33-10-rear-axle-final-drive/HKkhxo2d

These documents show that BMW now only recommends their special version which is SAF-XJ with FM Booster (part number 83.22.2.282.583) which is what we would recommend.
This is a lot more money due to it being a Genuine BMW Part Number supplied fluid.
However, we keep plenty in stock and ready for immediate use.