[nascarmechanic]

DO NOT use WD-40. That stuff only lubricates, not penetrates to loosen rust. As the others said, use the PB Blaster, available at most auto parts stores. Using that hammer may be tricky on an aluminium rim. At my shop, we always use a dead blow and beat the wheels from the back side. Less chance of visible damage and you are hitting the wheel in the direction it needs to fall off.