As you might expect the bevel box was discussed at the recent M3W focus group.
I don't want to pre-empt the outcome of the recent focus groups (which will be sometime after the Aero group focus group next month) but feel it worth letting you all know that MMC are not ignoring the BB issue.
MMC have been working together with Quaife to investigate the cause and have so far concluded it is most likely down to a very small variations (well within production tolerances) on the gears - possibly as small as a couple of microns on some gear teeth. This would explain why some are quiet then noisy or visa versa and also how some respond to changing oil and some don't.
It also accounts for the comments about needing to keep changing noisy boxes until you luck into a quiet one.
The MMC NVH kit may be ugly but it does apparently stop the noise - anyone on here with the NVH kit able to comment?
MMC have been working on the known M3W issues including exhausts, bevel boxes (and previously steering, chassis and compensators) without shouting about it. At the focus group we did suggest that they could share more of this info with owners.
The Quaife responses look like they are quite correctly protecting their client confidentiality and so they cannot comment directly.
