Water in my hydraulic oil?

I changed my hydraulic oil in the spring, to some very expensive john deere hi gard stuff because i was told it was the best in the buisness. The stuff i took out was dark in colour.

The hi gard that i put in was dark in colour, now its gone creamy, which i hear is because it has water in it.

Any ideas on how the water got in?

I did steam clean the tractor,which i am wondering if the pressure might have found a small hole and got in there.

Could it be the range selector rubber seal thing on top?

It is cracked badly, but it always has been, so i cant understand how the water didnt get in there before. Saying that it was stored undercover before, and rarely got wet.

Thanks for any suggestions

Ben

I work around things that change altitudes. Can really see the condensation thing when something is at 65 below zero and 5 minutes later 100 above. Water runs all over everything (inside and out). Only way to keep it out completely is total hermetic seal, dry air positive pressure from within, or keep it hot.

Since most of the gearboxes are empty cast iron space, they are prone to water contamination. That's why it is recommended that you change your fluids on a periodic basis. Colder the climate, worse the problem.

It's the same thing in gas tanks where it is suggested that you keep your tank full to reduce condensation; especially in the winter....but you don't want your oil sump full.....to costly.
Mark