When should a driver refrain from passing a truck on the right?

A driver should refrain from passing a truck on the right when the truck is signaling for a left turn because this situation indicates that the truck is preparing to move into the left lane. Trucks, due to their size and length, have blind spots that can make it difficult for the driver to see smaller vehicles on either side. If a truck is turning left, it may need to occupy the right lane more than usual to make the turn safely or may swing wide, putting vehicles in the right lane at risk. Therefore, when a truck is signaling for a left turn, it is both safer and wiser for drivers to avoid passing on the right to prevent potential accidents.

In contrast, passing a truck when there is a double yellow line would violate traffic laws, as double yellow lines indicate no-passing zones. If a truck is in motion, passing may generally be acceptable under the right circumstances, provided it is safe and legal. There are specific rules regarding the passing of large vehicles, and saying there is no restriction when passing a truck on the right misrepresents safe driving practices in various situations.