Answer:
Upon leaving the Sunshine Coast, take the M1 motorway which leads down to Brisbane. Stay on the motorway to cross the GateWay Bridge, and this continues on as the major highway down to the Gold Coast. You do not need to go through the main city centre of Brisbane at all. Depending on where you are leaving from the Sunshine Coast, and your final destination on the Gold Coast, the journey will take between 2 and 3 hours.