there was a myth about plastic impeller in the water pump but i think it was disspelled in this forum... run the search on this topic and see if changing the water pump for a newer impeller is warranted... the myth was that the OE used plastic for the impeller and some aftermarket folks have come up with metal (aluminum?) impeller... when you replace the hoses, you already have half of the front apart, might as well replace the pump... on my 2002 4.6 i had watercooled alternator - what do you have on the '01 4.4? the '06 4.8 does not have watercooled alternator...