you need to buy a wind back tool. it puts pressure on the piston at the same time you rotate it. you can buy them from garage tool suply outlets like sureparts etc
ian
January 2010
on callipers that incoperate hand brake mechanism the piston has to be wound back,some require piston pushing back whilst winding it to engage the screw mechanism.
k
December 2009
Some pads will just push back using a G clamp. BUT some others are THREADED design at the same time, LASTLY to confuse even more some are Clockwise thread some are Anti clock thread .
You could always ask nicely a Kwik fit. fitter, especially if your car has got ABS fitted