More than likely, the seals are out of the bull pinion bearing cages, and will need replaced. Not a terrible bad job, but just takes a while. It will make it a lot easier to remove the foot boards, to get at things. You'll also need to drain the transmission oil down below the bottom bolts holding the brake chamber on, as the hole goes clear through the transmission case, and oil will run out, when you remove it.
Only remove one bull pinion cage assembly at a time, as internal parts will drop. The bearing cage assembly is held in with several tapered head screws, with very large Phillips heads. I replaced these with tapered head screws with hex type, that you use Allen wrench type sockets to re-install. They only need to be torqued to like 15 inch pounds, but tough to do with a Phillips type head. You'll need to remove it, to install new seals. Seals 5-6 years ago were $15 to $18 each, depending on where you buy them.
The discs will be oil soaked too, but you can boil the oil out of them with a propane torch. I hung the one's on mine on a rod clamped horizontally, to my press setting outside. You definitely want to do this outside..!! Light the torch, and go in circular motion, on the surface of the disc's. They will start smoking, and oil will begin to drop from them. Just keep going until they stop dripping oil. Let them cool, then finish cleaning with spray brake cleaner. Once they dry, rough up the surface with medium grit sandpaper. You'll need to clean up the actuator plates also. 2 springs hold them together. Clean the steel balls, and grooves with choice of solvent. The manual says not to lube the balls, but we've found over the years that a very light coat of never-seize makes things work smooth, instead of grabbing.
When you go to re-install the bull pinion shaft bearing cage, you'll need to protect the seal lip, when sliding it back over the grooves in the shaft. Get a roll of electrical tape, and starting at the inside end on the shaft, just where the grooves end, and the smooth surface where the seal rides, start wrapping the shaft, from the inside out. Wrap clear past the end of the shaft, and leaves a couple inches of tail sticking out. Then, coat the tape with oil. Carefully slide the bearing cage in over the shaft, being careful not to invert the seal lip. Once it is torqued in place, grab the end of the tape, and spiral it off. You can the install the outer brake assy. IIRC, when I did my 310B (same brake assy.) I managed not to tear the gasket behind the brake assy., and re-used them. All parts are still available through Case/IH, and aftermarket suppliers if you need anything.
Here is a link for more than several manuals for the 530. I found it several years back, when the backhoe I bought was thought to be a 530, but turned out to be a 310B. Lots of info there in PDF form, and should also cover your loader.
http://home.microtech.com/mikef/530CK/manuals.php
