Originally Posted by Evilokc

Attachment 364064removed my heater core today. I have never done this before. I did what any modern person would do. I watched youtube and searched this forum. the biggest argument seems to be if you have to remove the dash or not. all parties seem to agree that this is a simple straight forward job except for ONE bolt. I agree that besides the ONE bolt its not too bad.
1) i didn't need to drain my coolant because my heater core had been bypassed.
2) removed passenger seat for room. you will be lying on your back. the seat studs WILL dig into your back at the worst times. just deal with it.
3) removed passenger side lower dash panel
4) laid on my back and started removing the 3 bolts on the air box cover
5) forgot there was a terrible bolt on the top
6) couldn't reach it so i removed the dash pad. still couldn't see it. put the dash pad back on.
7) finally saw that i could remove the ECU bracket and let the computer sit in the floor .there is a little black computer box right by the ecu. it can also be removed with two screws. this gives you a lot more room. this gave me enough room to reach up and around the top of the air box.

8) once i located the bolt it took about 25 minutes to remove it due to the angle and position. there is no room for you to use two fingers. you wont be able to turn it with your fingers at all. you can touch it to locate it but that's it.
the tool I used with success was a 3/8 ratchet with a wiggle and 9/32 socket. I broke the screw loose with the wrench but due to room only got a few turns before I ran out of room. I then removed the ratchet and turned the wiggle and socket by hand until it came out. it was a pain in the *** and I had to stop several times to rest my arm but its just a bolt. take your time and it will come out. you can now pull the airbox cover off and see the heater core.

9) removed the 4 bolts holding the heater core. they are easy to reach with a small extension.
10) removed the two hoses on the fire wall. be careful with these. they are heat sealed after all the years. remove the clamps and then use a small flat blade screw driver under the edge to help release them. gently twist and pull them off. try not to shake or wiggle them. that will easily break your heater core tubes.

11) finagled the heater core out. its a tight fit but will come out. remove it from its bracket. you will need to put the bracket on the replacement heater core.
NOTE-{ I thought my heater core wasn't leaking but after I cleaned it out and looked it over I did find a water stain where it had been leaking. }

12) I slipped the new heater core into place without the bracket into the air box to make sure it fit. i was able to set the bracket on to verify that with the heater core in place the bracket holes lined up.
13) attach bracket to heater core.
14) install heater core with bracket back into airbox/firewall. when i connected the heater core to the bracket the holes were way off. turned out that the heater core tubes weren't going through the firewall enough. i pulled the heater core back out and put some lubricant on the tubes and on the rubber grommets in the fire wall. my lovely assistant pushed and wiggled from the cab side while i pulled on the tubes from the motor side and it slipped right in. the holes lined up perfect. try not to damage the tubes when you pull on them. slow steady pressure. be careful not to cause a new leak.
15) install the hoses on the fire wall. this should be easy.
16) with the dash and airbox still apart i tested everything. i looked for leaks, made sure all of my blend doors were working as they should. lubricated the blend doors. although the air wasn't going through the vents without the airbox cover being installed the system would still blow under the dash. i was able to get cold and hot air blowing. so i knew there ware no leaks and i had heat. technically this was when i declared victory. as soon as i felt heat i felt like a winner.
17) time to put it all back together.
reinstall the airbox cover. this is the most time consuming part because we are back to THE BOLT. i installed 2 of the 4 airbox bolts loosely to make sure everything was lined up before i went for the terrible 4th bolt on top of the airbox. the trick for me was having the 3/8 ratchet with a wiggle and a magnetic socket. there is very little room to start the bolt. i could easily locate the hole and i was able to poke the screw into the hole but when i tried to put the socket on the bolt would fall out of the hole. with the magnet i could get the bolt started and was able to tighten it up far quicker than i thought. maybe 10 minutes.
18) at this point i tested the system again. the airbox is a big part and i wanted to make sure that with the heat a/c system back together everything was working correctly before i put the rest of the dash back on. it was
19) reinstall the black box and ecu.
20) reinstall kick panel and seat.
21) add coolant
22) hi five yourself and everyone you see. you have completed a big job.
this felt like a big job because its tedious. being under the dash is a pain in the...well everything if your tall. however it really wasn't that bad. the one BOLT is difficult but not the worst thing ive ever dealt with. using the right tool will make your life a lot better. i had a little trouble getting a good fitting replacement heater core. i guess there are several different cores that have the same part number. make sure to take your old core with you to the part store to make sure its right. if the tubes are off by just a few degrees the heater core wont fit. you CAN do this. don't be afraid. shops are charging $800 for this. i think my total cost was about $40.