Wire brush all over, clean out hub crack with sharp knife to let oil down between wheel and hub. Spray real good a few times in day, come back tommorrow. Use big mall to hit TIRE only, back side if you can. It shakes and vibrates alot, helps break up the rust seal.
I've also used hydraulic jack turned on it's side, turn wheel all the way one way, push on it more with jack and board against wheel, base on frame or whereever you can get good push. If it doesn't pop off right away, leave pressure on it, and try more oil and sledge trick again. Usually pops off then! Just oil it and leave hammer there, hit it when walking by once in awhile!
