First time I heard this squeak It was very faint and wasn't very consistent. Like everyone my guess was the top control arm bushing. Replaced that even though I realized it wasn't worn out, there are guides on tube which shows that it fits this squeak. But the annoying thing came back even worse. Then I brought the bottom control arm ball joints to replace. When I removed the wheel the bump stop has slid from the top, which I tried to fix.and I heard a smiler sound
I tried moving the shock and It was loose from the top. Then like anyone I tried to tighten the nut on top
which was pretty tight and broke the hex on top
Then I saw the worn out bushing, I can't believe some German engineer thought it was a good idea to put this form kinda thing on a top mount of a such a heavy car
Then I ordered a new one and cooked up my own mount from an old slipper sole from my wife and a garden hose
which held up nicely
So once the parts arrived I thought of making this DIY guide for everyone
First take out the tools trey and cover
Take out the 4 hook points with torx bit and two small screws on the loading guard.
Once done peel off the weather stripping and pull up the plastic load guard with 4clips on the bottom carefully
Then remove the side panels by removing the plastic rivets and pulling down, be careful of the clips on top, you might have to put your hand behind the panel and move the clips
Once the panel is remove you can access the top nut under the rubber cover.
Now this is where it gets tricky. I'm sure there some BMW took costing big $ but you can use a 7mm and a spanner. In my case I just hold the shaft with one hand and use the ugga dugger On the nut and it comes off easy.
Now jack up the car, it's just a case of pulling down on the shock and replacing the parts
Now tighten the nut to 50nm and everything back