The 6.2L Coolant Fan is not directly driven. The engine fan is mounted on the water pump shaft and is driven by the same belt that drives the pump. The purpose of this fan is to provide a flow of air thru the radiator. It incorporates a thermostatically operated fluid clutch in the fan hub. This allows the fan to turn less slowly when the engine is cold or when down-the-road driving supplies enough cooling air to control coolant temperature. As coolant temperature rises, the hot air passing through the radiator causes the bimetallic spring at the front of the hub to expand. The spring moves a plate, allowing the working fluid to pass into the working chamber. The fluid resists the free rotation of the fan hub and the fan turns faster. See Figure 2-45.