Is there really a ‘need’ to replace a seemingly perfectly functioning (no leaks, no overheating) water pump during normal maintenence? I have a 2006 F150 4.6L with 138k and no known maintenence history that runs and drives fine but given the unknown history I’ve been going through most everything normally done and have reached the last thing on the list, the Cooling System. Since everything seems fine I planned on just flushing the coolant, replacing the Thermostat and calling it a day, which would be nice, or am I just being lazy wanting a long drawn out project to be over with

(oh, the Belt and Pulleys seem fine, which I would have also done if I had gone so far as disassembling while doing the Water Pump)

 

just an opinion: id do a thorough flush, then resume driving. but have all parts (pump stat belt and all pulleys/tensioner) on hand. then do all when you feel like it OR when any one piece needs to be done.

you may be surprised how many rounds of flushing it will take before system runs clear. find fordtechmakeuloco video on diy flush.