Good video! Watched it twice.
Okay, I have all the other sleeves and the Mechatronic adapter on order from FCP, also the service kit for the diff and the transfer case. The kit I ordered for the diff says it is for the front position. A search for a rear diff service kits yields no results. Hmm.

 

Yes, both differentials. On my car, easy peasy. Transfer case, damn near impossible to remove fill plug.

 

Did you replace the drain and fill plugs on both diffs and the transfer case? How did you end up removing that difficult fill plug? No wonder a BMW indy shop quoted me $275 for the transfer case service. He must take components off to reach it.

 

If memory serves me correct, my front diff has a drain and fill plug, the rear just a fill plug - so, I needed an extractor. Needless to say, you will need a fluid transfer pump. I own a few. One for the transmission, one for the diffs, etc.

For the xfer case, I had the dealership do that. I could not find a way to get to the fill plug without dropping the xfer case itself, which I believe involves dropping the exhaust. Near as I could tell, the dealership did neither.

I haven't been under my car in quite some time, but the next time I am, I want to check the access of that fill plug. It takes an X mm Allen key. Not sure if it will work, but I saw a post somewhere, for something, that involved removing (punching out) the stubby Allen bit from an Allen bit socket (does that make sense?). I bought a cheap set from harbor freight just for that purpose. Thought is, that there is enough space to insert the stubby Allen bit, then turn it with a wrench.

As for $275, not bad considering that mine takes 0.6 L, but the damn fluid is like $70/liter or thereabouts.

Again, word of caution. When replacing the mechatronics sleeve, make sure that you are able to extract it, not take it out, but extract it. I was unable to, and had it towed to the dealership. It was surrounded by the same, or similar, devices or supports that block the fill plug on my xfer case.

In my case, all I need is a mm or so of extra clearance. Will simply file down one of the objects that are obstructing me at present. By the time I do it again, my car will have 150k on her, so.....

 

If you want, send me a private message and I will give you my phone number in the event that you are working on something and get stuck. Sometimes I am on these boards multiple times a day, other times not for weeks. Also, there is another forum, bimmerfest dot com, that is usually more active. I am on both. There are a few things specific to the xi's that I can probably help you with. For the more generic stuff, I believe that there are more than one BMW mechanics who are active on the other site.