The hydro will last just fine if you are changing it now. You will have a higher chance of a axle failure, or hub failure that you will of a lubrication failure.
I have personally owned and still do own eaton 1100's that had over 1700 hrs on original fluid and filter. Fluid and filter were nasty. They work fine.
I have personally owned and still do own eaton 1100's that had over 1700 hrs on original fluid and filter. Fluid and filter were nasty. They work fine.