Might I suggest...
...before yanking the dash, take you truck to a shop and have the cooling system pressure tested. That will confirm any leaks.
Also, the blend door is electric; the mode door is vacuum operated. If you can hear the blend door moving it may be OK. On the other hand it may not be sealing fully and allowing cold air into the chamber. In that case you WILL have to pull the dash to repair. However, you can remove the glovebox and feel for the actuator to move and give a clue whether things are kosher. Another also, is if you get warm air on one side of the dash and not the other, the diverter is sticking/inop.
Good luck.
The only reason i didnt go with your heater core idea was the mechanic i took it too says its good! I wont lie i dont know how to do this swap, i dont know whats what and i bust my ass 40 hours a week for 8.50 and hour with no money to pay for it or the extra time on my hands!!
I just figured that wasnt it since a professional told me it was good.
Thats why he tells you it is good, so he can rob you of more money to try to find whats wrong, then tells you it was the heater core all along. Thats why no one does any work on my truck except for me. You will never see any of my vehicles at a repair shop unless it is for a alignment.
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2000 Dodge Ram Sport 4x4, 5.9L, custom air intake, 33x12.50R16 Maxxis Buckshot Mudders, 3 inch bore glasspack, chrome bars, 3 inch lift, Rancho Steering Stablizer
Just woundering guys, Hope I dont interrupt/take over this post. Just wanted to know if you can access the 2 right vents if you take out the glove box? or would I have to take ou the air bag/dash?
WEllll i have the same issue i get lukewarm air and no cold in summer but hey im not complaining and i live in chicago where its pretty cold, hopefully this summer i get a garage where i can get my hands on and not be rushed tryign to do it before the rain gets there lol. Oh doesnt look to hard when its simple plug and unplug unscrew i can give it a go done the radio unit a few times so cant be that bad jus time consuming.