Abstract: A cooling system for an off-highway vehicle includes a heat exchanger (e.g., an engine coolant or hydraulic oil heat exchanger) and a fan mechanism for flowing air along a flow path through the heat exchanger. In the improvement, the fan mechanism is a centrifugal fan mechanism and is substantially the sole means for flowing air along the flow path. That is, there is substantially no ram-urged air. The mechanism includes a housing and a fan in the housing. The fan has forward curved blades, thereby to reduce system noise. A preferred fan has a depth-to-diameter ratio not in excess of about 0.4 and, most preferably, not in excess of about 0.25. An alternate embodiment includes what might be termed a split-discharge arrangement wherein air blown by the fan is discharged along two paths.