Will not heat up correctly
so here is the new problem.
Just replaced the head gaskets, Thermostat and heater control vale.
The truck is no longer over heating, but now it wont heat up correctly. It heats up to the appropriate level while it is idling, then about a min later it drops to just about cold. While running down the road it is running it runs colder than it should also. So Im wondering what could be causing this. Keep in mind it has a brand new thermostat. oh and yes I got the heads milled and replaced both head gaskets.