the motor for the doors is fine. i hear it working when the engine isn't running and i change it from heat to cool.

 

Local to fargo by chance? I have airlift 2 for bleeding coolant systems

 

nope, 4 hours away in minot. gonna let it idle up with the bleed screw loose and the cap off. should do the trick.

 

ok just checked the level again and the overflow tank was down by the minimum line and the radiator was a little low as well. guess that it won't take to much persuasion to get the last bit of air out. gonna let it sit overnight again and see what happens in the morning.

 

ok, it's been a couple of days and the radiator and the overflow tank levels haven't dropped at all. i've checked the blend door motor and it's working fine. the blend doors are moving like they're supposed to. the core is getting warm, even after it's first started. i ran the truck inside the garage up to full temp and still only a little warmer that luke warm. is it possible that the core is still clogged and the shop that flushed it didn't do a good job at it?

 

So now you have NO AIR in the coolant system since the coolant level is steady.
How about try this: Start engine cold and warmer up the engine without turn on the blower inside the cab. Monitor (by hand) the temp of the two coolant hoses connected to the heater core. If the heater core have good circulation you should feel like both hoses the same temp. When the engine is at operating temp the hoses should be hot to touch. If you have the same temp, now turn on full heat at max blower speed inside the cab to see if you have heat inside the cab. If still no/little
heat you have problem with temp control. It could be the controller or the blend door that mix the hot and cold air.

 

I know I keep harping on it, but did you check all the doors...besides the blend?

 

This a shot in the dark but would you by any chance have a vacuum leak on those horrible plastics lines that can affect your desired aiir flow for the AC/heat. Could be a leak onenofnthe vaccum lines having something to do with this. Me

 

Dude...it's an 8yr old thread. It's probably gone or scrap by now...

 

Haha... not only that but 3rd gens don't use vacuum for the HVAC system.

 

Exactly. They all use actuators anymore. SMH...