Do you have an e-tag? If not you will need to obtain an E-Toll pass to follow this route - read through this site to see how it's obtained.
This is this route I would take. Note I have dodged using the NorthConnex tunnel. I much prefer using the Pennant Hills Road rather than pay the $8 to save a few minutes.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
Should be better these days with a lot of traffic now going through the new tunnel. Three years ago when I towed our van both ways the tunnel was still being built - it would have been worth the $8 to avoid the dozens of traffic lights, and coming back south we had the school zone speed restrictions!
If you do chose to take that road, then make sure you use the middle lane or right if the traffic is a bit light. The right turn into the start of the Newcastle Expressway is from the two right lanes - the left goes straight ahead. If you miss the turn it will be very difficult to turn around and come back.
Don't let Pennant Hills Road scare you. I had my 25 year old son tow our 19.5 foot van the full length of the road from Parramatta to just shy of the expressway. I rode shotgun and had him drive in the left hand lane all ther way. It was his first time driving my 4 wheel drive and the first time he had ever towed a van and he did it with ease. You just need to trust yourself.