How to get the old heater core out?

LEELOO74

MEMBER
2005 FORD EXPEDITION
5.4L
V8
2WD
AUTOMATIC
164,000 MILES

I have my dash apart and now I am stuck trying to figure out how to get the old heater out. Do you have a diagram of the bolts I need to remove to get it out?

Thursday, December 11th, 2025 AT 1:55 PM

3 Replies

CANNON1349

MECHANIC
864 POSTS

Hello,
If you have the dash out then you should see the black HVAC box left attached to the firewall. The box should be removed by removing those bolts from the firewall. Hopefully you have evacuated the A/C system because the evaporator will need to be disconnected for removal. I will attach a picture of the heater core panel on the box to look for.

William

Image (Click to make bigger)

Was this

answer

helpful?

Yes

No

Thursday, December 11th, 2025 AT 5:15 PM

LEELOO74

MEMBER
1 POST

I need to know where the bolts on the firewall are. Do you have any other diagrams that show a more complete breakdown of everything needed to replace the heater core?

Was this

answer

helpful?

Yes

No

Friday, December 12th, 2025 AT 8:29 AM

KEN L

MASTER CERTIFIED MECHANIC
54,217 POSTS

Here is a video to help you do the AC work, you will need to remove the heater box plenum so start by draining the engine coolant.

https://www.youtube.com/watch?v=4EqdrBVb0sY

You will need to remove the dashboard and the heater box is held in by screws inside and outside at the firewall. This is a big job but if you take your time you should be able to get it done. If you have problems, please upload a short video or images so I can help you. Check out the images (below). Let us know how it goes

Images (Click to make bigger)