The new permanent replacement strut for Auckland's Harbour Bridge is finished and being driven to the city for installation overnight tonight.
The steel strut - nearly 23-metres long - is being delivered in two pieces.
A like-for-like replacement made in Whangarei, it's painted to match the rest of the bridge.
All southbound lanes over the bridge will close from 9pm tonight until mid-morning tomorrow.
One lane in either direction will also close from 5pm tonight to prepare the site.
Due to the closure, buses from the North Shore to the city will stop at Akoranga bus station from 8.15pm.
A shuttle will take passengers to and from the Birkenhead ferry wharf as an alternative.
Waka Kotahi / NZ Transport Agency is advising people to follow the sign-posted detour routes and allow extra travel time from the North Shore to the city centre.
Even if the new strut is successfully installed tonight, the bridge won't be fully open until tensioning work is completed - which will take a few days.