My truck is a 2004, since I have it the heater is not blowing a lot of heat during winter, this not realy a problem for me but my wife and my kids dont realy like the cold. I change the thermostat, I put a rubber mat to close 75% of the rad, the T is rising like normal but the fan is blowing cold air most of the time. Where I work I drive some newer cummins, 2006, 2007, and they blow heat like hell, the T just start to raise and the fan blow hot air. I dont now if some door in the blowing system are broken or what, last summer I check if the motor move the door when I move the control and everithing was looking fine, Yesterday it was -35 C here in Canada and the cab start to warm up after 1/2 hour drive... dont now where to check next...

 

not sure if it occurs on 04 model.the recirculation doors break and fall down on blower motor blocking air flow,do you have good air flow out of vents.drop down blower motor and you can look up inside and see recirc door.how many miles possible plugged heater core.

 

Sounds like the blend door issue. Mine sorta failed late 08. It would squeak when I turned the key to "on" when it was cold. But the bigger issue was the mode door. No heat went to the floor, as it was all sent to the windshield. Bout $800 to get er fixed. Have to take the entire dash out, steering column, evac the A/C. Was more in labor than it was in parts

 

Last summer when I check if the motor was working when I change the selection, I figure that if I want to check the whole system I have to put the dash apart. If I have to do that I going to be pist off at dodge, it's not something normal to have problem with, I have a 1984 F 150 and the ventilation system work fine, so why a 2004 truck need to be put apart for a problem like that,dont make sense

 

if recirc door is broken u can remove it when blower motor is out.you just wouldnt have recirc mode anymore.if u can have someone evac a/c dash and heater box can be removed in bout hour.you dont hav to remove dash just move passenger side up on to seat.whole
assembly has to be loosened though.

 

I will check that, my blower seem to push enough air but the heat is not wath is suppose to be until the T reach is max, and some time if the T is high the air pass from hot to cold. I dont now.....

 

ok so I have a heater issue that seems like the same issue. My truck was blowing hot air fine two days ago with the temps at +3-10f now that its -10f here the past two days the air blows face floor and defrost just fine but there is no hot air. Switching the t-stat from cold to hot the blower slows and then ramps up again but no noise of a switch.