water in power trim and tilt reservoir

[Tashtego]

Tilited my port 2004 225hp 4 stroke unit up and pulled fill plug for the trim tilt.
Very milky oil causing the trim to work very scratchy..... Is this a seal issue ??
Would it be the seals for the two small piston rams on either side of the main center piston ??? These are under water when the boat is sitting in the water,
ther's no signs of anything leaking....

[boats.net]

If you can't see which seal is leaking then replace all of them.

[1989200HP]

pwr trim ram is leaking

on my 1989 200, one of the rams is leaking - a few q's - can this fix be done in the water? do you recommend replacing all seals or just the upper most and the cap? how difficult is this job?