We are in Ballina, wanting to head to Glen Innes, Tamworth on way south, towing 22ft caravan. Don't mind travelling south on Pacific Highway to cross over to New England if it means less mountainous and windy road. In no hurry to get there.
The lesser of the evils IMHO would be Ballina - Lismore - Casino - Tenterfield not as hilly as the other options nice drive reasonably good road
Ballina - Grafton - Ebor - Armidale isn't a bad run either because it bypasses the range near Dorrigo.
A bit more hillier is Ballina - Grafton - Glen Ines nice drive though.
My favorite for scenery, but lots of steep hills is Ballina - Port Macquarie - Walcha - Tamworth. I've done this with both towing a caravan and with the motorhome.
I defineately wouldn't do with a caravan Ballina - Coffs Harbour - Belligen - Dorrigo - Ebor - Armidale as the road from Belligen to Dorrigo is near vertical!
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Steve, Di & Ziggy We named our Motorhome "Roadworx" because on the road works "On The Road Again" Ford Transit with 302 Windsor V8 conversion, C4 Auto, 9 Inch Ford Diff All Lighting L.E.D., 260 Amp/h AGM, 530 Watt Solar + Kipor Backup Gen.
I don't know of any highway that will go from the coast to the New England with out you having to cross the Great Divide at some point which unfortunately will mean sections of winding road. I have used both the Waterfall Way from Bellingen and the Oxley from Port Macquarie and they both have sections that you said you would like to avoid. I have never used the main highways further north such as the Bruxner or the Gwydir so someone else will have to advise you on those.
Done all the roads from Pacific to New England from the Southern most right up to Warwick. Not really a good one. Met a local in who lived up near Tenterfield and her comment was the same. It's really what type of evil you want. There is no easy way. Late 2015 pulled the van up thru Bellingen, Dorrigo to Armidale. The road to Dorrigo is smooth but twisty & very steep (as noted). Take your time on that and enjoy the scenery. It's prettier going down. The road from Dorrigo to Armidale is bouncy & twisty.
Last year I bit the bullet and went thru Sydney to get from Melbourne to Coffs & back again. There is only 10km of non-freeway. Do it on a Saturday or Sunday, keep in the middle lane and follow a truck. Surprisingly easy.
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GRANDPARENTS & GRANDCHILDREN GET ON SO WELL TOGETHER BECAUSE THEY HAVE A COMMON ENEMY
I'm not sure what your worry is all about. The roads ate all full two lane roads (except for a few bridges and very short lengths of road.) All rigs that are an good order and not overloaded are quite capable of negotiating these roads. You man be down in 2nd gear on some of the inclines but this does not mean the vehicle is struggling, it just means it is doing some heavy work. Doing a bit of hard work does more good than harm, it blows the cobwebs out of the system.
Do some armchair driving with these time lapse journeys.