[grimlock]

So my car was at 3.5yrs and 18k km city driven everyday, way past BMW's recommended first change at 2yrs, but I figured that was very conservative.

Anyways, it's very easy, sorry no pics:

1. buy 2L of the BMW OE DOT4 1L
2. 11mm box spanner
3. I used a suction tool, lots of other DIYs using pressure method also

4. remove plastic cover and three pins holding it in place, top left under hood
5. remove cap and suck all the fluid from the reservoir, I could not remove the mesh guard but that's enough. careful-brake fluid eats paint.
6. refil to the same level it was before
7. remove furthest wheel
8. uncap rubber nipple, attach suction, crack it open!
9. keep checking and refil reservour before it goes to the bottom

It took ages (total 3.5hrs) and I bleed about 0.65l from the furthest, then 0.35, 0.25, 0.2 - I am not an expert.

I read about the different methods, pressure vs. suction.. however I accidently slipped the suction off once and the fluid continued to drip slowly - the way it is designed I think is neither are required except to speed up the process, without fear of air getting into the lines. The brakes were fine afterward.

The old liquird was barely noticeably darker than the new - no comment on water content etc. I don't think I'll change again until 4-5yrs at least.

There you have it, a piece of cake - just takes a few hours.