thank you for answer!

I am trying to found now not to expensive differential, but what I found it is used and the price is 1000,00 EUR is it that to expensive ???

For now it is not urgently for me but I'll start for preparation.

I see the "kofer" I miss the price wich one is it ? is it possible to make these tool ? my father working in one factory wich one is specialized for metal stuff. maybe I can try to make one.

But I read in one post, that you have problem when you driving more than 40km/h wit active 4x4 ? what kind of problem can he provide, except spending tire.

For wich price you become your new differential ?

sorry for interrupting, and thank you for helping

1000.-€ is much to expensive. In UK (eBay) you can have a new one for 750.-GBP (without a part of the electrical clutch).
Or an used one for 300.-GBP (complete rear X-Trail T30 axle)

Peter has problems, because he works with 12V and much more than 2,8A.

Important! Do not switch on the X-Trail diff. on dry road with grip. Then you'll kill the clutch in short time.

I can take pictures of the special tools if you want. The price is round about 200.-€ for the whole box. But I think it is difficult to build a own one.