A section of State Highway 29 over the Kaimai range between Waikato and Bay of Plenty is down to one lane while crews work to clear the scene of a fatal accident on Wednesday evening.
A Te Awamutu man, 61, died after his truck and trailer unit went down a 20-metre bank on the Matamata side of the range at 6.25pm.
A crane is being used to remove the truck and police say the terrain means it's a difficult job.
The work is expected to be completed by 4pm on Thursday.