"Not needed. If the water pump goes it's extremely easy to change. Drain the radiator, pop the belt off, remove 2 bolts - and the pump is in your hand."

Unless the idiot people that owned the truck before you broke off one of the bolts and drilled another hole through it and into the block right beside the old one, rather than extracting the old bolt and doing it right. Happened to me,,,

 

If your coolant looks bad, a good flush is good. The extended life coolant is best. Always use a coolant conditioner for initial fills, then once per year. The conditioner will keep the PH correct and prevent corrosion and break down of the coolant. It also prevents cavitation of the coolant around the cyl walls which will errode holes thru the cyl. It keeps the complete cooling system in good working order. Semi's that use extended life coolant and conditioner can run 1,000,000 miles or 10 years and have a perfectly clean rad and water jackets in the cyls and head.

 

Now that's quality workmanship!

 

Cavitation is a PowerStroke problem created because PowerStroke uses sleeves (the shock created on on fuel detonation causes bubbles to form in the coolant and then they burst causing pitting and ultimately a pin hole in the sleeve). It's the only reason I drive a Cummins (not subject to cavitation) instead of a PowerJoke. If our trucks are rode hard and put up wet they are still good trucks. A PowerStroke that has been run even a few thousand miles without the coolant conditioner may be on the verge of loosing a cylinder to cavitation. I know this is an old post but just needed to add my 2 cents for anyone else searching.