Mechanics

HEATER CORE

1999 Chevrolet Silverado • V8 4WD Automatic • 123,000 miles

How do I replace a heater core in a 1999 Chevrolet Silverado?
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Thaz6969
January 4, 2011.



Here is what I could find.

Disconnect the negative battery cable.
Drain the engine cooling system into a clean container for reuse.
Disconnect the heater hoses from the heater core.
Remove the instrument panel storage compartment.
Disconnect the electrical connectors, as necessary, that may be in the way.
Remove the center floor air distribution duct.
Remove the hinge pillar trim kick panels.
Remove the blower motor cover screws and the cover.
Remove the blower motor screws and the blower motor.
Remove the steering wheel and the steering column (standard & tilt).
Remove the instrument panel fasteners and pull the instrument panel back far enough to gain access to the heater assembly.
While holding the heater assembly against the firewall, remove the screw located on the interior side near the evaporator pipe, if equipped.
In the engine compartment, remove the 4 heater assembly-to-chassis screws and the 2 heater assembly-to-chassis nuts.
NOTE
Removal of the heater assembly may require the help of an assistant.

Remove the 7 heater cover-to-heater assembly screws and the cover.
Remove the heater core from the heater assembly.

To install: Install the heater core to the heater assembly.
Install the heater cover and the 7 heater cover-to-heater assembly screws.
NOTE
Installation of the heater assembly may require the help of an assistant.

In the engine compartment, install the 4 heater assembly-to-chassis screws and the 2 heater assembly-to-chassis nuts. Torque the screws to 17 inch lbs. (1.9 Nm) and the nuts to 25 inch lbs. (2.8 Nm).
While holding the heater assembly against the firewall, install the screw located on the interior side near the evaporator pipe, if equipped. Torque the screw to 97 inch lbs. (11 Nm).
Install the instrument panel and the instrument panel fasteners.
Install the steering column (standard & tilt) and the steering wheel.
Install the blower motor and the blower motor screws.
Install the blower motor the cover and the cover screws.
Install the hinge pillar trim kick panels.
Install the center floor air distribution duct.
Connect the electrical connectors that were disconnected.
Install the instrument panel storage compartment.
Disconnect the heater hoses to the heater core.
Refill the engine cooling system.
Connect the negative battery cable.
Run the engine to normal operating temperatures; then, check the climate control operation and check for leaks.