Power Steering fluid fro MileMarker?

I was just pulling some stumps out with my 10,500 MileMarker winch. Have had it for several years. Noticed that it mostly stopped working after a while. The power sterring fluid was leaking out of the cap. Fluid seemed to be thinned out from the heat of operation. Let it cool down while eating and it started working normally until it heated up again.

Do I, or can I, need to change fluid types to make it stand up longer to winching? Have only used factory recommended type up till now.

Factory fluid. Might want to pick-up a cooler.

Rev