Here is a link to Case Construction for the 480F.
Case construction king loader backhoe | Case CE | MyCNHi US Store Scroll down, and find the brake category, and it will show views of the components of the brake system.
I have a 480C, and remember when redoing brakes on mine, I remember reading on later series, master cylinders used hydraulic oil, not brake fluid. If brake fluid is used, instead of hydraulic oil, it can damage the master cylinders. On my 480C, one brake line was rusted through, but the other was good. It also had very good pedal, yet no braking action. I bought 2 new aftermarket master cylinders through Joseph Industries :
Remanufactured Transmissions, Torque Converters, Engines - Joseph Industries , which eliminated part of the problem. They were the least expensive that I could find at the time. This was in 2012, and they still work great, so they are decent parts.
I also got new slave cylinders from them. At the time, only a few more dollars, than what most wanted for a rebuild kit. I also installed new brake lines, but opted to make my own from NiCopp line, as Case wanted $75 each for preformed lines.
Beyond that, on my 310B, the model I had before that, the bull pinion shaft seal was out on both sides, and had the brake discs soaked with SAE 90, making them pretty well useless. An old Case mechanic showed me how to "boil" the oil out of the brake discs, saving buying new ones. Simply hung them up outside, and took a propane torch to them, and literally boiled the oil out of them. Being they were bonded type discs, I was afraid it would break the bonding, but he assured me it would not. Worked like a charm. I could not believe the amount of oil that came out of them. Let them cool, and did a final cleanup with brake cleaner. Buffed with a Roloc medium gasket removal disc, to rough it up a bit. Made a world of difference, and would actually lock up the wheel, if enough pressure was applied to the pedal.
If those seals are bad, you can tell by looking at the bottom of the brake chamber housing. If there are drops of oil hanging below the housing, where it bolts to the transmission housing, the seals are bad. If there is no sign of oil, still might be worth pulling the brake housings, as a lot of dust, and dirt/silt can get in there, and keep it from functioning right. I also bought new 1" balls from Joseph Ind., as mine were rusted/pitted beyond cleaning up. I see now, those ball bearings are now $13.58 through Case/IG Ag., probably more through Case Construction. At the time Case Construction was 10%+ higher on the same part, through Case/IH Ag.
Using the above link to Case Construction, find the part number of anything you need, copy, and paste Google to search for aftermarket parts. You can find the Case Construction dealer price, by selecting a local dealer. I assure you, you'll be shocked at some of the prices. Joseph Industries had all the parts I needed in stock, and were shipped/received promptly. Fortunately, I'm only 90 miles from them, and anything I ordered by 10:00 a.m., was on my porch the next afternoon, by 2:00 p.m.
The last time I ordered from there, I spoke with a woman, and she knows her stuff. Give her the OEM part number, and she'll have it on it's way in short order. You can shop online, and compare, but imagine they still have the best prices out there.