How to Replace the Heater Core in a Chevy Silveradoby Contributor; Updated November 07, 2017
Items you will need
Clean, covered container
How to Replace the Heater Core in a Chevy Silverado. Replacing the heater core in a Chevy Silverado is challenging and potentially quite frustrating for a beginner, but still relatively simpler than performing the same procedure in other vehicles. Make sure you have a wrench, screwdriver, a clean covered container for coolant and a full afternoon to follow these steps.
Open the drain at the bottom of the radiator on your Chevy Silverado, and drain the coolant into a clean container that can be tightly covered and set aside for reuse. Then disconnect the negative battery cable and, if your Silverado has air bags, wait at least 2 minutes before performing further work to prevent accidental air bag deployment.
Disconnect the heater hoses from the heater core. Also disconnect the temperature control cable and the mode control cable from the heater case assembly. You'll also need to remove the instrument panel carrier, and be prepared to disconnect any electrical connectors that may get in your way. If you do disconnect electrical connectors, tag each end of the connector to ensure you don't get the wires mixed up later.
Remove the screws and nuts holding the heater case assembly in place, then remove the assembly and place it on a work bench. Remove the screws from the cover, open it, and extract the heater core, which looks a little bit like a waffle made out of graph paper with a couple tubes sticking out of it.
Return the heater core to the case and screw the cover into place. Return the heater case assembly to the vehicle and mount it in place, tightening the mounting screws to 35 inch pounds of torque and the nuts to 80 inch pounds.
Reconnect any electrical connectors you may have disconnected as well as the mode control cable and temperature control cable and the heater hoses. Replace the instrument panel carrier, then reconnect the negative battery cable.
Refill the engine cooling system and bleed air from it as necessary. Run your vehicle up to normal operating temperature and check for coolant leaks and normal climate control operation; remember that the heater may not actually produce heat until your vehicle is at normal operating temperature.