I'm glad that's what the problem was... Looking at the pic of the old pump, it didn't look bad, but it was obviously not circulating as it should!

Good job and I'll have to keep that in mind for future reference!

Mitch

 

Mitch, thank you for this post. I got the same truck I bought few days ago. Just for preventative maintenance I am doing the water pump and the belt .
I also decided to flush the cooling system and replace the thermostat. My antifreeze was original from 1997, nice and dark.
The truck has 164K.
This post was very helpful and thank you for the pictures.