*** Caution *** Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink ant that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old. Heater Core 1. Disconnect the battery ground cable 2. Drain and recycle the engine coolant. 3. Remove the instrumental panel. 4. If equipped with the 5.4L 4V engine, remove the junction block splash shield. 5. If equipped with the 5.4L 4V engine, remove the bolts and disconnect the cable ends from the starter relay. 6. If equipped with the 5.4L 4V engine, remove the junction block bracket. 7. Disconnect the heater core hose couplings. 8. Remove the retaining screw and remove the A/C plenum demister adapter. 9. Disconnect the vacuum line from the A/C plenum demister adapter. 10. Remove the heater core bracket. 11. Remove the 13 plenum chamber top retaining screws. 12. Remove the plenum chamber top. 13. Remove the blend door assembly from the case. 14. Remove the heater core. 15. The installation is the reverse of the removal.