Water in the oil

[ruskie34e36]

Hey folks,
This seems to be a come-and-go problem for me.. When I first bought the car, checking the oil, you'd see the tell-tale sign of water/oil sludge on the very end of the dipstick. After a while, and a few oil changes (flushed the system with some seafoam), I stopped seeing it. Also seemed to help almost eliminate the famous E53 oil consumption (I also let some seafoam sit in the cylinders overnight). So far so good. Mileage up, oil consumption down, no water.
Almost three years later, I am seeing the same problem again (water).
Went to change my plugs this morning, and inside of the fill cap had some water sludge, looks almost like lard, but a bit more yellowish. It was, however about 30 degrees outside. So i get why it would solidify. Oil itself looks good, I am positive the headgasket or anything that major is not blown. Just seems to have water in the system.
I've tried conventional oil, and synthetic. Anyone had this happen? Is it another "acceptable" issue as per BMW? Im starting to think if there are any separators or whatnot that can be cleaned/replaced, but wanted to get the opinion of the community here.


On the side note - getting ready to replace the fluid in the front diff soon, and will pull the skid plate down. Ive looked up the parts (bolts are single use), but the diagram seems to list two sizes that go thru the plate. # 2 & # 4 on the diagram. Everyone says there are 6 bolts total, but they are all the same. Last time I was under there, I remember 4 big bolts, which would be the M12, seems like. My question is which are single use then?
Frnt axle support, wishbone/tension strut BMW X5 E53, X5 3.0i (M54)