SA的车开去墨尔本，去长期居住不换牌行不行，求解答呀

By law you have to change to a VIC driver's license if you reside in VIC over three months or permanently. It is free. If you change your driver's license to a VIC one, you will have to change your rego as well. Before that, you car need to be taken to a roadworthy test, which will cost you money. I live in VIC country side and keep my SA driver's license and rego, but there is a lot of toll stuffs in Melbourne. Go to VIC road for more information. It's quite clear there. If you do need to change it, change when your rego expires.