Well..was driving down the highway and turned on the heat, and smoke started flying out of the vents..got to where I was going and took out part of the dash to see if there was any burnt wires and nothing.

Fast forward today..it still does it off and on, and while it smokes it also fogs up all my windows..well stopped by a buddys today and he said he thinks its my heater core because smoke wouldn't fog up my windows like that..I'm guess he would know being hes a firefighter..fast forward to now and Googled signs up of a bad heater core and yup..I found this
How to Tell If Your Heater Core is Going Bad | eHow.com

Number 2 states: "Look for abnormalities at the vent or defroster ducts. Look for puffs of smoke coming out of either one of these. Check to see if the windshield fogs up while or after running the heater or defroster."

Which is exactly what its doing..so has this happened to anyone else and it turned out to be the heater core? Just how bad is it to change one of these? I know you have to pull the dash off..that shouldn't be to hard..with all screws, the steering wheel is fine where its at though right? Once that is off is much harder? A buddy of mine that works for Ford said he would help me but I'd like to get an idea whats going to go down. -

Yeah this happened to me last fall. All it was the heater core for me.
What heater setup do you have? If you have the high out put setup all you have to do is unbolt the casing that holds it, seperate the to halfs and replace. I'm not to sure on the standard heating unit but accoding to autozone it should be about the same. The most your going to have to remove form the interior of the truck is the glove box. -

idi Tony's Sig:

85 F250 with the pump turned up. In the process of doing a four wheel drive swap.

Okay..dumb question how do I tell what heater setup I have? Not sure what you mean by "high output setup"

If its not the high output setup can I still get away with just removing the glove box? But I don't see how you can get to it by just doing that..I'm under the impression you have to remove the whole dash..

I had a windshield installed today on it and almost as soon as it was installed it started to fog up with moisture ..so I'm pretty sure its the heater core. AND it fogged up the windshield with the heat OFF. -

Does or did your truck have A/C? I dont think you can have the HO heater and A/C. I did the heater core in my 85 last year. The core is on the passenger side in a case behind the glove box. You just remove the GB door and a few brackets and a cover panel to get to it. -

Sycostang67's Sig:

1993 F-250HD SC XLT Lariat 4X4 7.3/ZF5spd ATS Turbo-173hp/335tq
1985 F-250HD SC XLT Lariat 4X4 460/ZF5spd
1986 F-250HD SC XLT Lariat 4X4 460/C6
1967 Mustang coupe 351/4spd
2006 Jeep Liberty 3.7/AT (Wifes rig)

I may have a working one if you need it.... Let me know -

EDP's Sig:

Air is what we do and Power is what the end result is!!!!!

It does have A/C, but its not hooked up..does that mean its going to be harder to get to than just behind the glove box?

---AutoMerged DoublePost---

Thanks for the offer, but my buddy hooked me up with a new one already. -

Well we tried putting in the one we bought from Advance Auto..doesn't fit. I guess the high heat output one is different, I guess because of the A/C..so took it back and have to wait till tomorrow for Advance to get the one that DOES fit.

We were able to take off just the glove box cover and the heater core cover and was able to get to it like that..we just hooked up a u-bend pipe till tomorrow till we can install the new one.

The one that was in there was shot though, had corrosion all over the side and was leaking. -

Okay..got the other heater core from Advance Auto today..it fit into the opening..but the pipes were curved and didn't line up at all with the hole on the firewall for the 2 pipes..

Tried going to Auto Zone and tried one they had ..and that one didn't work either.

Can someone tell me what the hell which one fits my damn truck? Its got the A/C, if that matters. -

If you have the old core out, take it with you to get the new one to compare them. They should have a program to show you a physical description and picture of the part if it's not in stock so you would at least know you were ordering the right one. -