After replacing fan clutch (which I`m certain it was bad) we still have the whine from engine compartment . After using redneck stethescope and throttling it up and down ,it most definately sounds like the noise is from pump. Recently I put a new muffler on the truck and after quieting down the sraightpipe theres noise I previously could hear because of droned out. Question is how much whine a pump should be making . Starts like a top cold or hot,doesn`t sputter or miss or smoke. Should I be worried that the pump is on its way out or do they get noisey ? Or should it be fairly quiet?