G'day teago,
Did the Plenty 9 months ago, not with a van but a camper trailer, the NT side is corrugated just about all the way (We shredded a front tyre on the Pathfinder and cracked a suspension mount on the camper.... all at under75km/h) , QLD side is smooth sailing. I guess if you take it easy you shouldn't have too much trouble. Hope this doesn't put you off !! It's a good trip - I'd do it again, just a bit slower next time!!!
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