How to Replace the Heater Core in a 1998 Ford F-150by Cecil Fontaine
Engine coolant runs through the 1998 Ford F-150´s heater core. Air passes through the core and then into the cabin of the truck, keeping it warm. Unlike the case with most cars, the F-150´s heater core is located behind the glove compartment, making it easier to access and replace. You can tell that your truck´s heater core needs to be replaced when the cabin no longer stays warm, even with the heat on at its maximum level.
Raise the hood of the truck and disconnect the cable from the battery´s negative terminal -- this will keep any electrical circuits from being completed while you are replacing the heater core.
Position a drain pan under the truck´s radiator and then remove the plug on the underside of the radiator. After all of the coolant has drained from the radiator, replace the plug and set the drain pan aside. On the firewall of the truck, find the heater hoses that connect to the heater core -- they are located on the passenger side. Use pliers to disconnect the heater hoses from the heater core.
Remove the screws that secure the glove compartment to the truck´s dashboard. With the screws removed, pull the glove compartment out and locate the heater core directly behind the glove compartment. The heater core is also held in place with screws -- use a screwdriver to remove them and then slide the heater core out and replace it with a new one. Secure the new heater core with screws and then re-install the glove compartment.
Re-connect the heater hoses to the new heater core (through the firewall, under the hood). Fill the radiator with the coolant that you drained in Step 1 and then re-connect the cable to the battery´s negative terminal.
- After you have replaced the heater core, run the heat on high for 10 minutes -- if the air is not hot, make sure that the heater hoses are firmly attached to the heater core at the firewall.
Items you will need
- Socket wrench
- Drain pan
- "Haynes Manuals: Ford F-150, F-250, Expedition & Lincoln Navigator 1997-2009"; John H. Haynes; 2009
- pickup truck image by Tonda from Fotolia.com