That is what I did, initially. Then I started the engine, moved the bucket and backhoe around a bit. If nothing else, the new filters had to get filled. Then I rechecked the level, I couldn't see anything so I thought the level had dropped below the glass. It hadn't, it went above the glass. I can't tell whether there is oil completely filling the window or whether it's empty, is there a way besides getting the coloring? Since I was expecting it to drop, I didn't bother to try to determine whether it was filled or empty. That's why I put more fluid in. I should have sucked some out then, it probably would not have been much at all. So the mystery is how could it go from being at about halfway up the window--about the correct level, and then after I start the engine, exercise the hydraulics, fill the two new filters, and after that, have the level be higher???
When I was draining the oil, I did drop the bucket and backhoe hydraulics as much as there was room for, that made more fluid come out, not a lot, but some. How do most folks deal with something like a backhoe, just assume the fluid in it is not significant enough to worry about when changing the tractor's fluid, so don't worry about whether it't attached when you do a change?
How much leeway do you have before you have to worry about damaging something? If the level is too low, will you see the temp start to rise? Or is that already too late? My temp gauge stays pegged at halfway no matter how hard I'm working the tractor or what the air temperature is, and being in central texas, that can get pretty high. That seems like a good thing unless I'm really confused.