The first hour or two are relatively quiet, with the "thrump thrump" of the engines sending many early risers off to sleep, either in their cars or curled up on ferry seats.
Those awake seem happy to chat, and from one I learned about the island's motoring history.
Before the current era of Japanese utes, Land Rovers were the vehicle of choice (1950s till 1980s) and there was also a Lada era (1980s till 1990s). Most of the Land Rovers ended up, a rustic reminder of the past, on the Schooner Bay property of marine engineer Ted Scott.
A conversation with two women nursing lapdogs, revealed one of the ladies to be Bronwyn Jenvey — a long-lost friend from Oxford Crescent, Upper Hutt.
Bronwyn and I lived next door to each other as 5-year-olds and hadn't met in 50-plus years. Considering the distance travelled, the ferry fare isn't huge ... it's about the equivalent of a couple of professional counselling sessions, and for my money a lot more stress-dissipating.
The unsubsidised service transports tourists, fuel, building materials, refrigerated food and sundry additional goods required to keep the island going.
Depending on conditions in the Colville Channel, the Island Navigator takes four to four-and-a-half hours from Wynyard Wharf to Tryphena, transporting up to 28 vehicles at a time.
It carries cars, utes, trucks, trailers, quads, boats, kayaks, even dogs and most vehicles were packed-up to the gunwales.
With passengers granted the run of the ship you can sit in your car, roam about or climb to the bridge and (except when leaving or approaching port) talk to he skipper. There's beautiful Gulf islands, seabirds and, occasionally, dolphins and whales to spot.
Sure, the Colville Channel can get choppy some days. Of my three crossings, two were millpond calm, one quite rough — I swallowed pills, put my car seat back and pretended I was sailing with Shackleton in 1907.
However you travel at sea, once you drive on to the island you'll have a ball visiting the three distinct communities: Tryphena in the south; Claris in the centre and Okiwi/Port Fitzroy in the north. They have the best beaches, hiking and biking tracks, locals are friendly and — with a map and some research — many fascinating metalled side roads to explore.
CHECKLIST
Further information: Sealink runs its Auckland - Great Barrier service several times a week. Check the website for seasonal sailing dates and prices.
• All scheduled sailings now depart at 8.00am from Wynyard Wharf.