Hey Guys

I wanted to toss this issue I have out there and see if I am anywhere near the ballpark on what needs to be fixed...

I have a 99 Durango 5.2L 4x4 with around 142k on the clock and last winter I was noticing that when the outside temp got below 20 or so degrees Fahrenheit, the heater would only blow air that was around 50-55 degrees.

If the outside temp gets above 30 degrees, the heater seems to blast heat as normal.

It would get so bad, that if I was driving in any sort of snowfall, the windshield would start to ice up... wasn't enough heat to melt the snow off the glass, even at full blast.

My first thoughts were thermostat, heater core, and vent doors not working properly.

I'm inclined to rule out the thermostat since the engine gets up to temp normally and I haven't had any over-heating issues this summer.

Do you guys have any suggestions before I start tossing parts at it??

Thanks!!

 

Kinda sounds like the t-stat stuck open possibly.