Hyd Pump brand

[MHarryE]

I checked the numbers on Mobilfluid 424, which is a high quality equivalent of most common tractor hydraulic oils. Viscosity is 55 CSt at 40C and 9.3 at 100C. Since you can measure temperature, find out what the temperature is when you have the problem. It could be the implement section of your pump is worn to the point it will not build pressure. Finding a replacement pump outside of the OEM is difficult when you get into multiple section pumps. Your tractor has a 14.53 cc implement section and 6.61 cc steering section. Fortunately the reliefs are external so that doesn't complicate the selection.