I am hearing a droning noise from the back of the car which increases in pitch as the car accelerates and seems at it's worst under acceleration. A faulty NSR wheel bearing has been replaced and there is no play in the other side.
What could it be?
Drive shafts and boots at rear appear to be fine, leading me to suspect the diff. Can the oil be changed in the diff or is it a sealed unit? It does not appear to be leaking either.
Also, what is the cambelt service interval on this car?