As well as installing vehicle monitoring devices, the trucking companies had also assured police there would be improvements to driver training programmes and a determination to work closer with transport agencies.
New Zealand Transport Agency state highways manager in Napier, Chuck Dowdell, said it was pleasing to see more companies leading industry behaviour.
"The only way to create safer journeys for everyone is for us all to get on board and do the right thing together," Mr Dowdell said.
Ms Pennell said police would support any initiatives that reduced speed on the roads.
"We pay special attention to heavy motor vehicles, as they are a big user of our roads. The open road speed limit of 90km/h is not a target and there will be occasions when that speed isn't appropriate."
She said police relied on professional truck drivers to "assess the situation and the conditions".