I'm guessing heater core. How hard is it to replace? Suggestions? It's on a 98 Expy EB 4x4, 5.4 with rear heat/air.

 

I've never changed one on an Expy, but with most other vehicles that I've had the pleasure of core replacement, it seems like the manufacturer starts with the heater core and builds the car around it.

Here is a link that will offer you another link that has some pretty detailed instructions that look to be from the Ford service manual.


http://www.f150online.com/forums/showthread.php?t=215665

Todd

 

I once changed the HC on a 1984 Mercury. After lowering the steering column and then removing the dash, I fished out what had encased the HC. It seemed like it was the size of a french horn case! I had only two screws left over when I finished!

 

I changed the HC on my '97 Expy. It was a long process, about 8 hours. I wouldn't say it's hard, but there are a lot of screws and bolts to remove. The entire dash must be pulled forward and the stearing column needs to be dropped. the link from ToddRG is the instructions I followed and they are great. Good luck!

 

Before going to all that work, check the hose and ghetto clamp that Ford put on the hose right above # 4 cyl. Those tend to leak and drip coolant onto the plug boot/hole and cause a #4 misfire code. Basically have to replace ghetto clamps with some good ones. It may very well be your heater core, but I have seen these hoses leak often.

 

I have a '99 Eddie Bauer Expedition and changed the heater core just last weekend. I mainly used a Chilton manual as my guide, but couldn't distinguish one particular diagram and gave up the first day. After a few minutes searching online for some help I ran across the article ToddRG mentioned. Use it from start to finish (including the helpful tips) and you shouldn't have any problems. I would also suggest cutting the tubing from the inside to get the core out...there's very little room to manuever to get to the hose disconnects. Changing the core itself shouldn't take more than 15 minutes. Getting to it is another story! My mechanic was going to charge me over $850 (mostly labor), but I did it in my driveway for just over $100 (new core was $60 at O'Reilly Auto Parts plus replacement antifreeze and a backflush kit).