How to Install a Heater Core in a 1995 GMC Sierra 1500K
- 1). Shut off the Sierra's engine and open the hood. Use the socket wrench to remove the battery's negative terminal.
- 2). Remove the two side bolts on the right-hand side of the dashboard, using a socket wrench. Open the glove compartment and remove its retaining bolt, located at the rear. Pull the glove compartment out of the vehicle. Remove the two bolts from below the glove compartment. Pry out the dash panel to the right of the stereo, using a slotted screwdriver. Remove the right dash liner by peeling it off. This will reveal the heater core.
- 3). Disconnect the two heater hoses from the heater core. Unplug its electrical connector and remove the drain valve by rotating it counterclockwise and pulling it off.
- 4). Remove the heater module. Pull off the heater case cover with a slotted screwdriver to reveal the heater core. Remove the two bolts that secure the heater core to the truck and replace it with a new heater core.
- 5). Reinstall the heater core cover by snapping it back into place. Reattach the heater module.
- 6). Reattach the drain valve and the electrical connector. Reconnect the two heater hoses.
- 7). Reassemble the dashboard and reconnect the car battery.
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