The tanker lay on its side on the road.
A milk tanker driver has died after crashing off a Taranaki road last Thursday morning.
The man died on Tuesday morning, according to a police spokesman.
Emergency services were called around 8.30am last Thursday to the crash on Skinner Rd in Toko where the driver was trapped in the vehicle.
Police Sergeant Andrew Russ said the fully-laden Fonterra tanker was heading south at the time of the crash.
"The driver has got to far left for whatever reason and lost control," he said.
"The tanker has crossed the centre line and flipped and rolled the entire unit."
The tanks on both truck and trailer had ruptured, with an estimated 20,000-plus litres milk spilled.
Russ said it had taken the best part of an hour for Fire Services to cut the 61-year-old driver free. The Taranaki Rescue helicopter airlifted the driver, who was in a critical condition at that time, to Waikato Hospital.
"If you’re loyal to them, they will be loyal to you."