No, fan should not be loud, except under special circumstances. My fan is basically "unhearable" except after the engine gets very hot - then the fan is 'locked' to the engine shaft and turns at much higer speed, according to the rpms, the purpose being cooling off the engine quickly. This should happen only when you're stuck in a traffic jam, or under stop lights and are not moving for some period of time (this is when engine gets hot). In normal speed driving the fan should rotate slowly and be very quiet because the engine does not need extra cooling. So, maybe the problem is with your cooling - maybe you're low on coolant and your engine is constantly hot (and therefore uses higher fan speed). Or maybe your fan is rubbing against something? Shut of the engine and try turning the fan - it should rotate freely, but not rotate by itself when you let it go. Hope this helps.