I finally figured out how to complete the heater core replacement. I've included my notes below for the benefit of other owners:
After much time and effort, I finally confirmed the Haynes Repair Manual is incorrect.
I spent approx 4 partial days replacing the heater core. Total of approx 20 hours. Much of the time was spent trying to figure out what to do or trying to obtain the correct tools. >>
The Haynes Repair Manual is approx correct up to step 14. Steps 1-14 describe how to remove the dash. >>
One problem I ran into is the driver side pivot bracket Torx screws appeared to be installed backwards. The screw heads were near the vehicle front and they pointed toward the vehicle rear. There was very little space by the screw head to insert a wrench. Removing the 2 screws was a pain. Before reinstalling, I drilled out the Torx screw nuts that were welded to the frame. I then purchased slightly longer bolts and nuts and installed the bolts from the rear pointing forward. The bolt heads are in the cab and you have easy access to them, so much easier to remove. The nut may possibly turn, but should be able to get a wrench in place and hold it. >>
After the Haynes Repair Manual Step 14, I did the following: >>
- The heater core is actually part of the heating / ventilation module. The heating / ventilation module must be removed and the heater core is on the rear of the module (front side of vehicle).
- Remove the blower motor resistor in the engine compartment. There are 3 screws on the cover.
- Using a socket and extension, reach thru the blower motor resistor cover opening and remove a screw from the firewall which holds the heating ventilation module.
- Jack up the front right wheel, put on blocks and remove the wheel.
- Remove the front right wheelhouse panel. This is the panel inside the fender. The radiator overflow tank is attached to the panel. I removed the elec controller mounted on top of the overflow tank. I could then loosen, lower and remove the wheelhouse panel with the overflow tank attached.
- Now remove the screws holding the heating / ventilation module.
There is one silver screw inside the cab on the lower right side.
There is one silver screw inside the engine compartment near the module top.
There is one dark screw near the center of the engine compartment firewall.
There is one dark bolt towards the center of the engine compartment.
The bolt has a nut visible in the engine compartment.
Remove the nut.
The bolt screws into the heating / ventilation module, but is not accessible in the cab.
There are 2 dark bolts inside the engine compartment near the lower left.
The bolts have nuts visible in the engine compartment.
Remove the nuts.
The bolts screw into the heating / ventilation module, but they are not accessible in the cab.
- When the screws/bolts are loose, pull out the heating / ventilation module.
The 3 bolts will be attached to the module and be pulled out with it.
The heater core hose clamps must be removed.
They will hit the firewall and prevent the module from being removed.
I purchased a Redi-Aire heater core from Advanced Auto Parts for $60. This did not fit properly. >>
I purchased an AC/Delco from A-Line Auto Parts for $115. This orig equipment and fit better.
The orig heater core had insulation tape around it. I added the tape to the new heater core. This prevents the core from rattling around. >>