this unit often gets the fan drive belt tensioner pulley over tightened, which puts un-needed side pressure on the hydraulic pump jack-shaft and u-joint, which can considerably increase engine noise levels. this tensioner does NOT need to be very tight at all, (just finger pulling on the tensioner is fine) since the only thing being driven by that belt is a fan blade, not like one that the fan and alt and water pump run off the same belt. you can also consider removing the belt, tensioner and fan, and replacing with an automotive after-market electric radiator fan.