Drivetrain - Rear Axle Grinding Noise On Low Speed Turns
SI B33 01 02
Rear Axle
July 2011
Technical Service
This Service Information bulletin supersedes SI B33 01 02 dated January 2009.
[NEW] designates changes to this revision
SUBJECT
[NEW[ Grinding Noise from the Rear Axle Differential during Slow Cornering
MODEL
E46 M3 from start of production
E60 M5 from start of production
E63, E64 M6 from start of production
[NEW] E85 (Z4 M Roadster), E86 (Z4 M Coupe) with S54 from start of production
2010 BMW M6 Convertible (E64) V10-5.0L (S85) Page 83
E90, E92 and E93 M3 from the start of production
SITUATION
A grinding noise may be heard coming from the differential during slow cornering. This noise is best heard during tight cornering situations; for
example, while parallel parking, driving in a tight circle, etc.
CAUSE
When the rear wheel speed differential varies during tight cornering, a slip/stick effect is created on the lining and steel discs incorporated in the
differential locking clutch causes a grinding noise.
This noise typically goes away as the locking clutch discs in the differential wear in.
The break-in time varies depending on driving habits; for example, tighter cornering (working the locking clutch) means that it takes less time to
wear in the locking clutch discs.
[NEW] CORRECTION
When this condition is verified as described above and afier performing the following replace the differential oil with the specially formulated
differential oil, BMW part number 83 22 2 282 583, if applicable.
1. Review the prior maintenance service history (DCSnet Vehicle History - Warranty Vehicle Inquiry) for one or both of the following:
Service - running-in check; and
Service - rear axle differential.
2. Confirm which oil is currently filled in the vehicle's differential:
Use the "MP Claims" button to filter and view the maintenance claims individually. Select and click on the corresponding "Claim Number" for the
applicable items above to proceed to the claim details - parts information.
If the vehicle's differential already contains the special formulation oil, the procedure outlined in this Service Information bulletin does not apply.
If the rear axle differential oil is eligible to be replaced with the special formulation oil, replace the oil and submit the claim as outlined in the
Procedure and Warranty Information sections of this Service Information bulletin.
Important:
Please see the "Note" in the Procedure section.
PROCEDURE
1. Drain the differential oil. Refer to the appropriate model repair instruction in TIS:
Main Group 33 / Subgroup 10 / REP 0011259.
2. Refill the differential with special differential oil as shown in the illustration below.
2010 BMW M6 Convertible (E64) V10-5.0L (S85) Page 84
^ Remove the seal (1) between the bottle cap and neck.
^ Pull the filler tube (2) out of the bottle.
^ Remove the cap (3) from the filler tube (2).
^ Insert the filler tube into the fill hole in the differential and with the bottle positioned under the output shaft, squeeze the bottle to transfer the oil
into the differential.
3. Road test the vehicle.
With the vehicle at operating temperature, drive in tight circles (20 circles in each direction), allowing the special oil to coat the locking clutch discs.
The grinding noise will decrease when the locking clutch discs are sufficiently coated. Some slight noises may still be heard after driving in tight
circles. Advise the customer that it will be necessary to drive the vehicle up to 600 miles before all noises are eliminated.
Note:
Vehicles that have had the differential oil converted to this special oil must continue to use this oil whenever a maintenance service or repair requires
the replacement of the differential oil.
PARTS INFORMATION
2010 BMW M6 Convertible (E64) V10-5.0L (S85) Page 85
