Check your ignition switch. They can fail intermittently when hot.

You positive it's the diff? There is a bearing that can go bad on the VC which gives you that noise and also causes vibration in the rear. Instead of taking the axles out and making stubs, I'd remove the VC from the torque tube and then reinstall the tube empty (need it there to align the diff prope...

Can you send a pic of the V70 walnut trim to trigtm(at)gmail(dot)com?