hi i am new to cliosport,i am doing this for my son as it is his car(he is away army duties)i went to fit new pads on the rear of car,took off caliper so i could push piston back but it only moved about 3mm then stopped ,it does not seem to be corrosion there seems to be some resistance there could it be anything to do with the handbrake linkage?.Should the piston just push back like they normally do ,or does the self adjusting mech on handbrake need resetting etc can some one please help many thanks tubby