02 Dodge ram 1500, 115,000 miles. Recently replaced radiator, water pump, thermostat, upper and lower radiator hoses after a 200 mile trip during October. The first time it got cold outside, I ran the heater and cold air blows (even after the engine is warm). Someone mentioned feeling the temps of the hoses to see if they are warm. The upper radiator hose is warm, but the lower one didn't seem warm. Any suggestions on where to start would be much appreciated.

 

Sounds like a clogged heater core, and you are not getting water circulating through the heater core. Do you have a problem with your vehicle running hot?

 

Yeah I say a clogged heater core. If your lucky you can can a fitting to hook up a garden hose and hook it to the line thats cold to black flush it. If not good luck pulling the whole dash. It was a complete pain in the ***.

 

I appreciate the advice. Someone mentioned replacing the radiator caps, that if they are defective, there may not be enough pressure to force the water through the heater core. Let y'all know what i find out.