#4 shot is more for ground-hog sized game. It'll toast up a groundhog nicely. But on yotes, like the others have said, it is probably too light, unless it's a very close-range shot.

#4 Buckshot is my personal favorite for a lot of things- I love flattening groundhogs out to 40 yards or so with it. I'm sure it would do the same to a coyote, but unfortunately I've never been able to test that out personally.