Funny noise from an auto gearbox X90

[Lulu]

Hello,
I'm new here, but hope someone out there can offer me some advice.
I have a 97 2 (rear) wheel drive x90 and last year had to have a new (recon) engine block fitted as there was a split in the original one. Shortly after, there was an internmittent faint noise - I would compare it to someone using a grinding wheel in a shed at the bottom of the garden.
Lately, the noise is more regular and goes for longer periods. Her mechanics (Paddy and Paul) think it is likely to be the gearbox. Does anyone have any other ideas, know of an automatic gearbox or know someone reliable who could restore the one she has.
Many thanks

[ScottieJ]

Have you checked the auto box fluid level? Might be worth changing it and making sure it's at the correct level.

Also would be worth checking the rear diff.

[Lulu]

Brilliant! Thanks a lot. The universal joint has now been changed and so far (fingers crossed), the grinding noise has gone. However, it means I can hear the other noises she makes more clearly!

Thanks for your help.

[ScottieJ]

Ah yes I completely forgot to mention that it could be a prop UJ that's gone dry! It's usually simple things.