Annual hydro fluid change?

[cheesegrader 433]

I'm looking for advice on the frequency of hydro fluid changes.

The manual recommends every 100 hours or annually.

Try as I might, I won't get 100 hours of use per year.

At 21 years old, my 520h only has 700 hours.

I would like to switch to amsoil this year, but don't want to change it every 40 hours.

How dangerous is it to change this hydro fluid every three years?

[Kelly 1,033]

I think you will be fine, but I would still change the filter every year and top off the oil, I also do not put many hours on any one tractor, so I've been putting synthetic oil in my hydros.

[Hydro 131]

I have never changed every year either. There are not the same issues with contaminents in the Hydro as there are in an internal combustion engine. I think it's more of a viscosity issue.

[sorekiwi 761]

I dont think I'd put 100 hours on even my mowing tractor in a year either.

Kelly's advice is probably good, although I dont change the filter every year. I usually change all the oils on a tractor as soon as I get it, and then the hydro's get an oil change and filter every 2 or 3 years.

Starting to think maybe I should change it a litle more often, my tractors sit in an unheated building so probably do get a little condensation buildup inside the cases.

[lincman 3]

I change the fluid on my 520H every fall, I put 50hrs/ year so just for good measure I change it, besides dad did it so I guess I got his habit. I put SAE 30 in it, seems to work alot smoother without any grunts.