Anyone got any idea please about this ?

1, What oil goes in Diffs

2, Drive shafts boots, Front o/s outer Has split anyone tell me please if cv joint is held on the same has any other car with a little round wire clip halfway down drive shaft splines to hub where it held in a very small groove. Or does subaru have its own way of retaining it

Any other ideas on this is are needed has i need to get it done asap. have done peugeots etc and fords loads of times but i would just like to know if anything different about Subarus design