Yep it goes uphill with a few bends for a few kilometres. Good wide road. Gradient is like many going inland from the coast - definitely noticeably uphill but nothing too drastic. People pulling vans up there all the time.
Have a look at this map Map of Hervey Range Developmental Road. There is some information there regarding gradients there. There is also a link to show you where the steepest pinch is.
If you are ascending the range you should have no problems unless your rig is out of tune or overloaded. If you are descending the range, slow down and use low gears to assist your braking on the steeper pinches. I have never found this road to be difficult to tow a van up or down.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.