It's acceleration and deceleration and low speed cornering, ive read in various places that some diffs are noisy but sometimes it makes some strange noises which dont sound too great, when cornering you lose confidence with it, As said the box was rebuilt with new bearings, before the box made grinding noises when the clutch was engadged but the diff never clunked or made a noise, but since the rebuild the gears a silent and the diff is noisy? Thanks for your response