Certain Vehicles to Be Driven in Right-Hand Lane. When any motor truck, tractor, trailer, or any combination thereof with a gross weight of vehicle and load of 10,000 pounds or more is being operated on any highway, it shall be operated in the right-hand lane for traffic or as close as practicable to the right edge or curb, except when overtaking and passing another vehicle proceeding in the same direction or when preparing for a left turn at an intersection or into a private road or driveway. Source: PL 3-61, § 1 (§ 512).