No heat and running warm

[stimpson]

Sounds like you have had one or more thermostat failures and air trapped in the system.

That's what I'm thinking. I'll try another Stat, and another purge.

Do you know what type of Tstat they put in the truck? Most of the good ones have a fail safe to when they fail they just stick open.

Don't know what kind. Pretty sure it's some what open. I could see coolant flowing into the tank on top of the radiator.