whats the smoke coming from?

i'll check all of those items guys. I have checked multiple times for rubbing from the wheel itself onto another part of the fender well. I don't see any leaks from the transmission that would be spraying onto the other car parts and smoking. whats weird to me is that the smoke is coming from the same exact spot(the rear driver's side wheel). The parking break looks good(not rubbing or dragging on the drums). On a 7 1/4 rear end how do i check the fluid level and add to it? never done that before.

thanks for all the ideas guys!