Hey guys its been around 20 degrees here and below everyday and my truck hasnt had heat and its finally getting on my nerves! the truck takes a long time around 20 minutes driving to warm up and when it does warm up it only blows out a small amount of heat when all of the fan controls are off but if i turn the fan speed up it blows out cold air. it's not low on coolant and i just replaced the thermostat and both of the heater core hoses are hot but the upper radiator hose doesn't get warm for some reason. im out of ideas and id love any and all input

 

Sounds like the common blend door issue. Check this post out.

https://dodgeforum.com/forum/3rd-gen...0-minutes.html

 

If the upper radiator hose is not getting hot its not the blend door sounds like a blockage in the system someplace. could be blocked heater core blocked radiator or bad water pump. I hope you put the t-stat in the correct way.

Sounds like the system might need a good reverse flush. You can do the heater core separate and the radiator separate or do both together.

What position does the temp gauge show? try a piece of cardboard in front of the radiator while driving and see if the temp will go up.
My first thing to do is do the flush and check to see if the t-stat was installed with the spring towards the engine side.

 

Did you burp the system. Could simply be a air pocket.

 

Air pockets usually make 'em run hot. You didn't mention: does the engine warm up? Sounds like the thermostat is stuck open.