its finnally given up pulled out the drive to day and heard soome rather grounchy noises and then no drive at all. though it will still drive with the prop diif in.
luckly mate of mine has a spair so my weekends sorted
I think its more than likely the centre diff because you can here it crunching when the diiff is still locked and crunches and makes all sorts of noises when its not. but i will still check the front diff