my heater works great but it just blows out front vents no defrost anybody have any ideas?

 

blend doors.

 

I agree.

 

Mine too, I been looking at, Heater Treater doors.

 

Check the vacume line beside the tranny dip stick,mine got pulled apart and never noticed it till I was dislodging the hvac box to fix problem myself

 

Huh! Never knew that... what year is your truck?



If it is working sometimes and not others, then I would suspect electrical or motors...

 

Under the dash the below the heater controls there you will find the vacume hoses to control the doors,it might of had the main hose come off,if these are in place than I would start on the doors,if you put your mind to it you can have the hvac box out in a hour or so.

 

The cannuk's truck is an 01, FWIW... may not be applicable in a third gen...

 

My blend doors haven't worked since the end of our 100 degree plus days of summer. So winter time here or in the panhandle of Texas your feet freeze till the heat finally sinks to your feet. I don't want to cut as instructed on their web site. I'd rather wait till (who knows how long) I can get someone to help me take apart the entire dash and then replace all of the doors. My mechanic would charge close to $2,000 for total work!! Ouch. Unless someone here this next summer is willing to help me out (maybe a free meal or two and a case of beer) @ a much lower cost.

 

Your "Mode Door", driven by small electric motors on your 3rd Gen instead of the vacuum of 2nd gen trucks, is most likely busted. Dodge truck HVAC units are prone to this. (Blend doors mix heated air with ambient air to deliver the temp you want)

Do a search here for "Heater Treater" and you will find loads of info on it.