The rear left side has siezed slightly on, causing great amounts of heat and has pretty much thinned the livin crap out of my axle grease in the hub. I'm having probs getting another caliper from a wrecker so I'd like to know if anyone has worked on unsiezing the piston, is it possible or worth even trying?

make sure your bolts arent too long rubbing on your caliper.

 

other than that, you should be able to free it up, by pushing it in and out, or pulling it apart and cleaning it up. unless its a giant rust ring inside the caliper on the bore, or piston, or your rubber is worn out, but if its not leaking, there is hope.