E90 E92 E93 M3 Diff Rebuild

Introduction:

Over time the E90 E92 E93 M3 Differentials can wear (as all mechanical components do), and some have developed the infamous 'M Clunk', some have bearing failures, and some make that annoying grinding noise when slow speed cornering and tight parking manoeuvres.

This 'wear' in the Differential comes from a mixture of some or all of these problems:
1. Poor maintenance (lack of oil change or incorrect oil grade).
2. Worn clutch friction plates.
3. Excessive back-lash (usually introduced during the Pinion Input Oil Seal change).
4. GKN 2nd generation LSD Cluster Play (seen at the left hand side Output Flange).

BMW say these Diff's are 'sealed for life' and they offer no spare parts for the internals.


Rebuild standards:

These Diff's are perfectly rebuildable and we carry out the following items on every build.

All E90 E92 E93 M3 Diff Rebuilds come with the following:

  • Professional disassembly and inspection of every internal component.
  • First stage cleaning and organise of individual components.
  • Medial-blasting of Main Steel Casing.
  • Media-blasting of Rear Aluminium Cover.
  • Second stage cleaning before painting.
  • POR-15 painting of Main Steel Casing (Black).
  • Spraying of Rear Aluminium Cover (Silver).
  • Third stage cleaning before assembly.
  • Professional assembly of original hardware pieces.
  • Professional backlash and position setup of Crown Wheel & Pinion Gears.
  • Professional preload setup of LSD cluster assembly.
  • Professional assembly of all new renewable items.
During all Diff Rebuilds we supply & install the following NEW parts:
  • 8x Clutch Plates.
  • 9x Clutch Intermediary Plates.
  • 1x Free plate 'delete' shim to reduce play on the left side.
  • 1x Pinion Front Bearing.
  • 1x Pinion Rear Bearing.
  • 1x Pinion Oil Seal.
  • 1x Pinion Crush Sleeve.
  • 1x Pinion Nut Lock Ring.
  • 1x Output Left Oil Seal.
  • 1x Output Right Oil Seal.
  • 1x Output Left Bearing.
  • 1x Output Right Bearing.
  • 8x Rear Cover Bolts.
Then during installation into the vehicle we use the following new parts:
  • 2x Exhaust Downpipe Gaskets.
  • 4x Exhaust Rear Mount Nuts.
  • 4x Exhaust Centre Plate Bolts.
  • 2x Diff Fill & Drain Plugs.
  • Castrol Transmax 75w140 LSD Fluid.

Prices: (all prices include installation and VAT).

Option 1: 
(No Longer Available).

Option 2:
OEM Rebuild as per list above 
£2,195.

Option 3:
OEM Rebuild as per list above 
PLUS New Wavetrac Limited Slip Diff (LSD)
PLUS E39 M5 Output Flange Pair (required when fitting Wavetrac)
£3,935.


Ratio change:

The E9x M3 7-speed DCT left the factory with a 3.15 Diff Crown Wheel & Pinion ratio.
This can be upgraded to a 3.62 Crown Wheel & Pinion ratio.

The E9x M3 6-speed MT left the factory with a 3.85 Diff Crown Wheel & Pinion ratio.
This can be upgraded to a 4.10 Crown Wheel & Pinion ratio.

The prices below includes the software/coding work required to tell the vehicle it has a different final drive ratio so the DME/DSC/DCT can function correctly.

Option 4:
(No Longer Available).

Option 5: (DCT)
OEM Rebuild as per list above 
PLUS used 3.62 Crown Wheel & Pinion Gear Set.
£2,795.

Option 5: (MT)
OEM Rebuild as per list above 
PLUS new BMW Motorsport 4.10 Crown Wheel & Pinion Gear Set.
£3,175.


Option 6: (DCT)
OEM Rebuild as per list above 
PLUS New Wavetrac Limited Slip Diff (LSD)
PLUS E39 M5 Output Flange Pair (required when fitting Wavetrac)
PLUS used 3.62 Crown Wheel & Pinion Gear Set.
£4,535.

Option 6: (MT)
OEM Rebuild as per list above 
PLUS New Wavetrac Limited Slip Diff (LSD)
PLUS E39 M5 Output Flange Pair (required when fitting Wavetrac)
PLUS new BMW Motorsport 4.10 Crown Wheel & Pinion Gear Set.
£4,905.

All our prices include installation labour, and VAT.

This is an exchange program where we specially build you a Diff to whichever spec you choose, before your vehicle arrives with us.
We then 
keep your current Diff which goes back into our exchange program.
(Alternatively, you can pay a £800 surcharge to have your old Diff returned to you).

To make a booking with us we require a £1,000 deposit for our Diff rebuild options.

If you would like to discuss Diff Rebuild options, or make a booking for this service, please Contact us and we'll be more than happy to help you.

Price includes VAT.


As the E9x M3 platform ages, there are increasingly more items which are deteriorating.
Here's an example video of some of the common items we find: