I thought I'd park this video here, as I recently experienced the gear failure on our 2005 x5 3.0i. Six months after the repair it's going strong with not a single problem!

Great video for the actuator. I changed that about 60000 kms before the transfer case failed. So change your transfer case oil and hope it lasts past 200,000kms.

I have now fitted a new transfer case to my car. I searched for one secondhand in Aust. and found one with only 60,000 km on it. Then I flew it back with me when i went to visit. Had that fitted and now that problem is solved.

But before I returned home other things happened. Now the rear suspension bushes have gone on the rear swing arms and I am waiting parts for that.
So just another problem to the list of problems another month of waiting for parts and trying to find someone who can fix it.

It was almost eaten a tyre so it is dangerous to drive like this.

BMW does not sell the bushes for the swing arms separately. So you have to buy a whole swingarm about $400 each. All up if I did this fix with their parts it would cost me over $3000. So going for aftermarket bushes.

A never ending source of Trouble is your BMW. Its all fixable as long as you have deep pockets.

Here's a quick 5 min video detailing diagnosing the gear failure:

https://youtu.be/Rn6fEjPcXzk