OK guys, here it goes...
My machine is unique because it came with a factory diesel. You have to verify the trans yiu have. the assembly number is stamped on the flange next to the firewall. (seen from the ground)
Mine has;
70142RHR model is 70142, R is right hand rotation (because it is a diesel)
E940907GD Serial 19
94,Sept
09 ,day 7.
When I tested mine I also had a 1/4" ball valve in line with the gauge, so I could close off the flow. Normally, the fluid passes through the steering box when not turning.
So, the 20-40psi might be right. Should run up to 200 to 300 psi under load.(valve closed)
I removed my trans just to make life easier, and to work in the garage. It's no big deal to remove it, you have to drain the oil in either case and its only three more hoses and couple of bolts.
I'm a ex welder by trade. I said no way to fix it, because of the way the relief bore was drilled and tapped. It was stepped drilled and tapped. 2" in was a smaller thread diameter to accept the threaded seat. The larger outer thread is for the plug holding the spring etc. My seat pushed the alumimum threads out into the return galley. There is no way that I can see fixing the bottom of this bore, Even a helicoil can't be used.
On buying else where... Eaton wants u to use their service centers. on the site I used my ZIP and nothing came close to here in the northeast. I bit the bullet this am and ordered from TM. U guys are lucky, because the diesel one is $100 more!!!
For mine, here is the links:
Parts
http://www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/dev_216878.pdf
Repair
http://www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/dev_216879.pdf