Here are a few photos of what, I’m guessing from interweb images, is Fire Blight. No leaves are affected, yet. The branches are drooping, which may have encouraged fruit formation, though there are a couple other branches with fruit as well. Cutting 8" below the affected area is basically cutting off half the tree, which I probably should have done on ‘day one’ anyway, but this was my very first fruit tree and I knew even less then than I do now. There are some groovy grafts in this half and even a fruiting crabapple branch from a NoID tree I saw in town one day…oh well. If this is serious and it looks like it is = gotta go, eh? This was a big box store purchase and I have no idea what root stock may be involved.
The two close-ups show both sides of the same area, and the two other pix show the affected branch from both sides. One higher branch is even drooping. At the bottom of the lesion we’re looking at bare wood.