Truck drivers on the M1 won't be able to live life in the fast lane from next month.
The state government's announced it is starting up a 12 month trial forcing heavy vehicles to use the two left lanes of the motorway between Kariong and Wahroonga from November 1.
The move aims to improve safety and traffic flow on the major road, which is used by more than 75,000 cars and 7,000 heavy vehicles daily between Sydney and the Central Coast.
Trucks and buses will still be permitted to overtake other motorists, provided they do not use the far right lane.
Drivers caught breaching the rule could cop a $337 fine, or be slugged up to $2,200 if a penalty is imposed by a court.