I'm the original owner of a 1997 F250 (light duty w/7 lug wheels) with the 5.4l motor with only 134,000 miles on it. It's been well maintained over the years including changing antifreeze every 3 years.

My question is what is the typical lifespan of the 5.4l motor waterpump? At 134,00 miles should I change the waterpump as preventive maintenance?

 

I would think not if the antifreeze was changed that often.
It has lubricant and corrosion inhibiter.
Also the antifreeze needs to be the type recommend by mfger.
My 02 has 285000, the coolant has been changed a number of times and pump is still working as normal.
It's when owners try to get around it by using straight water that the damage is done to the pump, corrosion from the block and heads, that collect in the radiator, that the damage accumulates over time.

 

Bluegrass, that's good to hear at 285,000 miles your waterpump is still good.