If you have a real wheel drive car, a lot of the crucial, mechanical action will be taking place behind you as you drive your vehicle along the road. This is because the energy produced by the engine has to be diverted through 90° before it can be transferred to the road wheels. Consequently, if you can hear some unusual noises from "back there" you need to pay particular attention, as something could be wrong with the transmission.
Most cars in the country of Australia will need a roadworthy inspection on a regular basis, to ensure they're safe for driving and aren't creating undue amounts of pollution and exhaust. If you need to get a new registration or are thinking of selling your vehicle, note a few factors to consider and keep in mind about these inspections and certificates, so you know all details involved and are sure to get this done in a timely manner.