The south east region of Queensland is a four wheel driver's paradise with an amazing choice of exciting off road adventures available. An excellent example of some great beach driving is the 4wd section of Bribie Island.
About 1.25 hours drive from Brisbane's south side, Bribie's 4wd beach is probably the closest sand driving to most Brisbane residents. From the southside the quickest route is usually up the Gateway Motorway, across the Gateway toll bridge and up to the Bribie Island turn off the highway, about an hours drive. This is followed by another 20 minute or so drive through some small townships, over the bridge to the island itself, through the town area over to the far eastern beach. There's a chance for a toilet stop or snack break at the small shopping area before heading along the beachfront road to the beach access point. There is a basic car park area at the end of this road where it is easy to pull over and let your tyre pressures down before heading onto the sand.
Bribie Island would be one of the easier sand driving experiences and you could almost do it without letting your tyres down or using 4wd mode but it is a far more enjoyable experience being set up correctly. I run my tyres at 18psi and have only used high range 4wd mode with the centre differential locked. With this setup my vehicle feels pretty much unboggable and makes the driving a lot of fun. I do carry some MaxTrax as well, just in case, as well as a snatch strap, rated bow shackles and shovel, although I've never needed to use any of these yet, not here anyway. Decent ground clearance is useful, sometimes the ruts in the sand going onto the beach are extremely deep, like 30 or 40cm, and you might see smaller cars get pretty stuck at that point. Having said that, you will see plenty of the smaller cars out on the beach so it is possible.
Anyway once you let your tyres down there is a 500m to 1km sand/dirt road down to the beach access point. This access track gets pretty soft in places and has some very deep potholes and ruts.
If you time your trip to around low tide you will have a pretty easy run up the beach. There is about 20km of beach to drive with a number of creeks, lagoons, and war era emplacements to stop and check out along the way. Just a few kilometres up the beach from where you come on is Norfolk Creek. This is a lagoon area that is excellent for swimming, kayaking or setting up a shelter for the day. It is very popular with families, being a safe haven for kids activities. Usually Norfolk creek takes the form of an enclosed lagoon, however after rain the creek can sometimes break through to the ocean creating a water crossing with creek water flowing out and/or tidal and wave flows in. This can become more treacherous in these instances so you need to take more care and know your vehicle's capablities more thoroughly. If you have any doubts just setup camp and enjoy the day here, though usually this is an easy crossing, or not even a crossing.
You will need to buy a Bribie Island 4WD access permit before you go and this is pretty easy to do online at the Queensland Government website: [Bribie Island 4WD Access Permits]