Water in tranny
 

Does anyone know how water or antifreeze can get inside tranny ?
It's all started from whine in transmission, and about 2-3 seconds delay to engage reverse. When I drained the fluid, it looked like someone have mixed some milk with it. I did put new filter and also drained fluid from torque converter, put fresh stuff inside and went for a test drive. It does shift fine, besides little delay into reverse, which I did not have before this.
I have removed two tranny lines from radiator, put my finger into lower one, and pumped some air into top one with bicycle pump. I was hoping to see bubbles in my overflow tank, but nothing in there. I'm assuming my tranny cooler is OK. I also did check for a breather on the back of a tranny, and it is there. I'm not loosing any water from the tank either.
Is there any other ways for water or antifreeze to get inside of it ??

1990 300E 722.358

Probably a leak in the tranny fluid cooler which is in the radiator. Its probably a very small leak.

Ditto...trans cooler in radiator is the most likely issue.

Trans cooler-radiator leak
 

2001 e320 55k
trans slips, remove top radiator hose, trans oil in water that was leak out top, MERCEDES SHOP replace radiator, drain trans oil, no more slip of trans, oil goes to top of water or you see it will be at top of your small exp water tank.

REPLACE THE T-SAT , MAY STICK CLOSE IF WATER IS DRAIN OUT FOR
REPAIR, ENGINE WILL BE VERY HOT IF NOT OPEN T-SAT AND MAYBE NEW ENGINE ALSO TOP AND BOTTON HOSES