Trucks and towing vehicles will have to make sure they keep to the 90 kilometre an hour speed limit this long weekend.
Police have updated speed cameras that can tell the difference between general traffic and trucks, caravans and towing vehicles.
AA spokesman Dylan Thomsen says the move will lead to safer roads.
"We know that every driver has been out there and seen somebody who's towing, or a truck driving who's going faster than 90 kilometres an hour. We know that it causes a lot of frustration for other drivers sometimes, so this is a really good thing."
Police have rolled out 45 new mobile differential speed cameras to replace the 31 currently in use.
- Newstalk ZB