I believe that it is a quite acceptable unsealed road most of the time ... depending on when graded and/or weather.
It is certainly a busy road between May and September - particularly at Birdsville races time.
This site gives a bit of an insight -
Route: Marree Via The Birdsville Track (520kms)
Once Australias most hazardous stock route, the Birdsville Track is still an unsealed road but maintained so that you can travel in either a 4WD or SUV with a caravan or camper trailer. The road conditions can vary and you may find yourself travelling over a diverse range of surfaces from sand dunes to gibber pains. Watch out for ponded water after heavy rains.
I would be putting the van through a pretty thorough testing prior to tackling the track - Ensure your "Road Service" provider covers the van. A tow out will cost thousands of dollars. We have done it on many "Safari " trips (average 40 vehicles) but always have had to require our safari mechanic fix several vehicles and Camper trailers en route. Travel with companion vehicle if possible. Do not attempt after rain.
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Possum; AKA:- Ali El-Aziz Mohamed Gundawiathan
Sent from my imperial66 typewriter using carrier pigeon, message sticks and smoke signals.
Picking the van up from Melbourne, before heading home. Are there some corrugated roads out of Melbourne that I can spend the day on? [so I can take it back for any remedial work that may present]
The big difference between the Cub & a caravan is dust ingress. Lots of caravans travel the Birdsville track, but I'd hazard a guess that they are mostly filled with red dust!
Big Red is not an obstacle on any track. It is not near either the Strzelecki or Birdsville Tracks. It is a side diversion option if you are coming across the Simpson Desert from the Dalhousie Springs.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.