7030 transferring hydraulic oil

I was using my 7030 to pull the bean drill today. Tractor has unknown hours and is new enough to me it hasnt done much field work, so history is hard to guess. Been doing great the last few days. Checked all fluids and went to work today, 3 hours later was running in 4th hi and suddenly stopped moving. All other hydraulics worked. I shut it down and found no oil on the transmission stick. I overfilled it and started it back up and seemed to be fine, got to the end of the field and level was already way down. I killed it, unhooked, and drove it a quarter mile home. Only had a little on the bottom of the stick when i got there. Had at least 10 gallon above the top sight glass in the rearend when i started draining before i plugged it and got a different tractor. Is this the seals trasferring in the hydraulic pump or something else? If its the pump, can someone with moderate skill level fix it with a seal kit or do i need professional help? What are the odds I hurt the pd by running it out? Thanks in advance.

It sounds like the oil seal between the transmission pump and the power steering pump. I used to pull the pumps and install the seal in less than a day. I had one special (homemade) seal driver for the seal.  I feel you have another issue to deal with because it is a 7030 tractor, and that is the fact that your scavenge pump may not be keeping up as it should if you are operating in up/down hills. This should be upgraded with parts from a salvage tractor to cure that problem. Maybe it has already been updated, but I have no idea. I'm not there looking at it.  Just replacing of the pump seal might not be the fix. You might get the dual pump assembly apart and find you need a complete dual pump assembly. You're never going to know until you take it apart.