"In the hyd part. In the pump--- P.S. fluid."
PS pumps use ATF. The only hydraulic pumps that use ATF/PS fluid is a DC powered electric pump like a snow plow or liftgate uses. Hydraulic pumps that are powered by PTO's ( the subject of this thread) use standard hydraulic fluid same as a tractor or off road equipment uses. The seals in these high pressure pumps are not made for ATF or additives and the clearences aren't generally the same either. PTO pumps may be gear, vane or piston design depending upon application requirements. But NEVER use ATF in them.
