Transmission Noise

[rjaxe]

The transmission on my Plus 2 S130/4 makes a rasping sound on the overrrun, sound fine in drive. I have just changed to Redline oils for the box and diff hoping for an improvement in noise level but if there is any it is only marginal. The gear selection is fine and I cannot detect excessive play in the diff/propshaft driveline. The car had been converted to Miller CV driveshafts some years ago.
Should I expect a significant difference in noise between drive and overrun? or is this a pointer to a developing problem? or do I live with it as a normal feature?
Any help will be appreciated.
Richard

[types26/36]

Could it be a vibration? check the diff is not contacting the chassis at the bottom, also check the engine mountings have not sagged are are broken.

[prloz]

Diff. drive flange retaining nut loose ?
Loss of pinion pre-load ?
Regards,
Peter.

[rjaxe]

Thanks guys, I will follow up your suggestions and keep you posted.