Which situation requires a truck to use a winch for towing?

Using a winch for towing is specifically required when a vehicle is stuck or in a hard-to-reach position. Winches are designed to provide the necessary pulling power to extract a vehicle from challenging situations, such as being stuck in mud, snow, or a ditch where conventional towing methods may not be effective. These situations often involve obstacles that prevent a standard tow, making it difficult for a tow truck to connect to the stuck vehicle.

In contrast, the other scenarios described do not necessitate the use of a winch. For instance, a vehicle on a flat surface can usually be towed using standard towing equipment without any need for the additional pulling power a winch provides. Similarly, a legally parked vehicle typically requires no towing at all, as there is no obstruction or hindrance that necessitates special equipment. Additionally, weather conditions such as a dry and calm day do not inherently influence the need for a winch unless there are other complicating factors present.

In summary, the situation where a vehicle is immobilized or hard to access is the primary context in which a winch is essential for safely performing a tow.