If the discs are scored due to the old pads metal then yeah they will need to be replaced as the discs will do the new pads no justice and wear them faster also a good possibility the discs may be warpped again not good for new pads. if the discs look smooth and have little of a lip around the edge then yeah pads can just be changed. next time keep an eye on pads about every three weeks average to notice the wear rate and change before scoring occurs. hope this helps. B)