I had the same probleme with a d7 48a and it was the stering cluch pump on installed on bellhousing had a broken seal.

You have things going in the right direction Barry.
The inlet relief valve is in the large valve body bolted to back of converter housing. It has two spools in it and a hose off of it back to supply trans with oil. If it's covered with dirt it likely hasn't been messed with of late so just make sure spool will move inside. This valve and a loosely mounted pump that blows it's outlet seal can flood torque like you have there.
Next thing to check is the trans input shaft bearing. It should hold the inputshaft and spider flange solid. If it has failed it could let the converter out put shaft move back(out) enough to allow the cast iron seal ring to run out of it's bore and not seal. The cast iron ring holds most of the charge oil inside the converter.
Later Bob

One more thing Barry, when you have the torque out check the crankshaft endplay, should be around 0.025 somethimes a bad torque can force the crank forward and take out the thrust bearing. A new crank seal would be nice too but only after you find cause and correct it. Check the magnetic suction screen and trans filter for metal before spending much money on it.
Later Bob

Hey Bob, I pulled the torque and took it apart. There's a big bushing or bearing in the back that is eat up, scored real bad. also the cage that it runs in is bad. I don't see any cracks anywhere so far. Just thought I'd let you know what I found.

Barry

Barry check over all of the inside surfaces for dammage caused by bearing failure or metal in the oil going through it. I think the gouged out bushing you say is where the cast iron seal ring runs. That ring is what holds most of the oil flow inside of the converter. If that ring is missing the converter under load can pump oil away from the inlet faster than the trans pump can supply it, dumping it all into the converter housing and the engine in your case.
Next thing to do is check the trans filter and magnetic suction screen for metal, don't want to put more money into a basket case. They can get a bit spendy rebuilding everything back of the flywheel on down to the final drives. If you do find much metal check the bevel gear shaft bearings. Take off pto cover and put bar behind the gear. AND also check the crankshaft end play, should be around 0.025" a bad converter can force the crank ahead and take out the thrust bearings.
Later Bob

Bob, if I can figure out how, I have some pictures for you. I checked the magnetic screen the other day, it had some metal, but I didn't think it was excessive. I will check the other items you mentioned. Thanks

Barry

WOW! Barry, I never saw one that bad before. Looks like she ran without any oil for a while. Might be best to try to get a good used converter assem. The piece that bolts into the housing complete. I would take it apart and inspect it before installing though. Also make sure the trans pump driven gear isn't starting to mill out the back plate. The gear in the housing that drives it and the hyd pump can get worn splines on the trans pump end and if it does it will force the driven gear back and eat trans pumps as fast as you can install new ones. If crank thrust measures good put in a new rear crank seal so you don't have to pull the converter again. Need installing tool to do it right. When you get all that finished put new yellow Orings on the tube feeding oil to the trans valve. Tube is in RH rear corner of trans under cover plate. Follow hose from modulating relief valve on converter to back of trans where flow Tee's off to steering valve.
Later Bob