Are you planning to go through Tarago or Braidwood Musketeer?
If you take the Braidwood route, theres 15 k's dirt road which is pot-holed and slow going if you are towing. Havent been on that road for about 3 months, so if its been graded recently it will be better.
The road through Tarago is the one we usually take, have towed a 15ft van quite easily over it. Theres 3k's dirt road which is dusty and stony but no problems. A low-level bridge (Oallen Ford) before Nerriga has a load limit of 5 tonnes which is ok for us, but a bigger van might be pushing it a bit. Its a few k's shorter on this route, and a lot less than through Batemans Bay.
Both roads have narrow winding sections and some climbs/descents, take it easy, drive to the conditions and you'll be fine.

We have done Canberra to Nowra in the motor home when we had it
but Fitzroy falls and camberwarra mountain are a bit tricky with some hairpin
bends etc , and a big tight one on top of Camberwarra ,

bout the best i can do for you..

others may have better suggestions

thanks for the info ,it sounds like the tarago road is the best road to go ,but how low is the bridge gerty if you remember ?

We've travelled this road frequently over the past 6 months, and have often stopped beside the river at Oallan Ford for a break and a cuppa. Theres usually people camped there a bit further away from the road. Idyllic setting, close to the Shoalhaven river, no amenities. Another nice spot is Tianjara Falls east of Nerriga.

ok great ,thanks everyone,as always good info

Travelled Braidwood - Nowra a few weeks ago on our way down to pick up the van. Road had been recently graded & for a gravel road, far better than most. Returned via Nowra, Nerriga, Tarago towing the van two days later, easy as run, to call the climb mountainous is definitely overkill compared to any other climbs I've done across the mountains - BT-50 towing a 2 tonne + van & there was only one hill I had to change out of 5th gear.

Darrell & Sandra