2002 4.7
Overheats after driving it for a while, but will cool down only if I keep the RPM's above 3000?
I have flushed, changed thermostat, cap, clutch fan. Is this the water pump?

Even when I am idle and the engine is almost in the red, I can rev the engine up and it will go back down. Thanks for your suggestions.

 

Probably, after having been through all that, especially if it won't keep cool unless you're moving.

 

water pump